Saturday 26 December 2020

What is corona virus ?

 What is corona virus ?

                                          
SCIENTECHPLUS

Hello dear all my readers ,

Today we are going to discuss and know more in detail all about corona virus .

So here first of all let we know that , what is the mean of word " corona " so the mean of the word 'corona' is derived from Latin language it means "crown" or we can say that in other words "wreath" .

So as you already seen that the photo or image of these corona virus . These image or photo of the Corona virus is approximately or we can say very close to seen like crown of the king . So that on the approximate looks of corona virus as like as crown , so that's why these virus got the name corona virus . 

The corona virus is a one type of virus . As same as corona virus , there are many viruses are exist on the planet earth . But one thing is that they are all in non-active in condition .

So among the all viruses , the corona virus is as known by the name SARS-COV-2 caused a world wide pandemic of respiratory illness which is called as or known as COVID-19 .

So let's know about , what is the full form of COVID-19 , so that the CO- stands for corona , VI- stands for virus , D- stands for diseases and the last 19- stands for 2019 novel coronavirus or we can say that '2019-NCOV'.

From where these corona virus come from ?

The corona virus which we also called by the name SARS-Cov-2 and the disease which happen by these virus is called as or known as corona virus disease or we can also called by the other name Covid-19 .

The coronavirus disease started from first week of November 2019 . The place from where these disease got to seen or we can say starting point of these corona virus disease is in South china , Wuhan sea food market .

In this Wuhan sea food market there are many types of flesh product are selling such flesh products such as dog flesh , hen flesh , pig flesh , snake flesh , bat flesh etc. 

So overall these the sea food market is believed outbreak starting point of these corona virus disease .

Before, the reality is that the corona virus is mostly founded in animals . And also these virus is only exist in animal species . In the sea food market in wuhan city, the place where all flesh products are put together in one place . So therefore , these corona virus got chance to jump directly to human species by the process called mutation .

So let's know about, what is mean by mutation ?

The mutation happen or occur when a DNA (Deoxyribonucleic acid) gene is get damaged or we can say changed in such a way that as to alter the genetic message which is carried by that gene .

So in your mind one more question is come that ,  in so much of animals from which specific animals these coronavirus come from ?

Here the answer is in bat mammal !

So here in this paragraph we are going to know all about , how these corona virus spread ?

So according to today's researchers , they know that the new corona virus spread through the droplets of released into the air, when any infected person or a living being cough or as well as sneezes .

So generally the droplets is not travel long distance in air , is all because of they are in heavy state . So that when any infected person or living being coughing or sneezing on the spot , the droplets of coughing or sneezing fall on the ground . So that's why physical distancing play a very helpful major role to stop the spreading of these corona virus .

So here the given is the some symptoms of these corona virus or COVID-19 ?

i) Cough

ii) Fever or we can say that chills

iii) The shortness of breath or we can say difficulty in breathing .

iv) The Muscle aches or we can say that body aches

v) Sore throat

vi) Diarrhea

vii) New fatigue

viii) Nausea or we can say vomiting

ix) Congestion or runny nose

In some rare cases corona virus or we can say COVID-19 can lead to severe respiratory problem , kidney failure and death also .


Wednesday 23 December 2020

Why we swing our arms when we walking ?

 Why we swing our arms when we walking ?

                                                  
SCIENTECHPLUS

Hello dear all my readers ,

Have you ever think about , why do we swing ours arms when we walking ? .

We do this action because we want dance when walking on the road ...???  Naa...h !

Yeah it is something unknown for all of us , but behind this concept there is some scientific fact is exist .

So let's known or explore in detail about this interesting and exciting scientific reason behind this fact .

So for understanding this concept or phenomena , first of all we have to visualize or do practical performance of this walking action .

So first of all what we do while walking ? , usually when we walk we take our first step and swing our opposite arm in the forward direction .

So the question arises here why we do like this ???

So for that concept something scientists are still trying and working to figure out , why happen like this ? .

So however as per taken so much of experiment , it was found that or come to the conclusion that when we swing our arms while walking we use 12 percent less energy , as we compared when we walking hold our arms still .

So it means that normal arms swinging is not a muscle-driven work . It maintain the whole body naturally without any much more effort . 

So instead this philosophy , some other experts even suggest that our arms swinging helps to balance ours body's rotational motion .

So what happen on the philosophy of body's rotational motion . So it state that when we put our one leg forward the pelvis twist or we can say that in other words rotates sideways . 

So therefore forward swing of our opposite arms or hands counterbalance this rotational motion of our body .

So that's why we walk very easily and comfortably .

So we hope you understand this concept very clearly and nicely " why we swing our arms when we walking " ? .



Tuesday 22 December 2020

What is 3R mantra ?

 What is 3R mantra ?

                                                
SCIENTECPLUS

Hello dear all my readers ,

Here in this blog post we will go to see and discuss about on the topic ' 3R mantra ' .

So let know about what is 3R mantra ? So the 3R mantra is stand for Reduce , Reuse and Recycle .

So you surprised so much , what is the use of this 3R mantra : Reduce , Reuse and Recycle . What is the purpose of it ?

So by using this method we can able to approximately change the world again to it's green zone environment . 

So these 3R mantras is very significant for the planet earth to sustain in his green environment .

So by following these three mantras we are able to make our nature eco-friendly .

So let's go to see more in detail about these three mantras .

So we take first of all Reduce mantra : If you think about there are many things which you don't need . So there are many things which you don't need , when you go to the market , mall etc.  is your plastic bag .

When you go to the market or mall you don't need of plastic bag for carrying the load , so in the place of these plastic bags you can use paper bags or clothes bag for holding load .

So than you can able to Reduce the use of plastic bag for shopping .

In your home , office , school , colleges , lift , university , etc. switch off the fan and light by doing these you save the energy and Reduce more consumption of energy .

So let's talk and discuss about on the topic Reuse mantra : Here the word ' Reuse ' itself declared it's meaning that to take use of things until gone fully non-use .

So how many things do you think we can reuse again or in other words that taken in our work second chance again and again instead of throwing them .

i) The piece of paper , which is only printed in one side page , we can use on writing on the other side of the paper .

So you have questions that which things in our home , to take in use again after used those things .

So the following examples of these Reuse mantras

i) In our home whatever old news paper is left , we can take in use to make new new craft for doing creativity .

ii) In case of plastic , we can reduce to use of plastic by not taking plastic with shopkeeper when we go to market . So whatever plastic bag left in your home try to Reuse that plastic .


Now here the last mantra is Recycle : Now in the Recycle process , we can follow this last steps to helping our nature to stay in it's greenery position . 

So how we can do this process ?

i) So simply what we have to do now , find out in your home which things in your home is Recyclable

ii) And after collecting those things sell it to the Ragman or in other words we can say that to sell it to the kabadiwala's .

iii) So these Ragman or kabadiwala's give it to the Recycle factory or we can say sell to the Recycle factory .

iv) After Ragman sell the Recyclable things to the factory , the factory Recycle your thing or material and than again these product come in a market for selling purpose .

v) So as we constantly continue this process again and again than there is no chance of collecting unwanted material in our environment which leads to harmful for the nature .


So we hope you understand this concept clearly and nicely " What is 3R mantra ? " .



Monday 21 December 2020

Why dogs can't eat chocolates ?

 Why dogs can't eat chocolates ?

                                                 
SCIENTECHPLUS

Hello dear readers ,

Here in this blog post we will discuss more about on this topic , why dogs can't eat chocolates...?

This topic is quite going to be very amazing . Because here in this topic some wonderful and exciting fact hidden behind this .

So let's start about on this topic " why dogs can't eat chocolates " .

So here in this chocolates and other cocoa products , these all products contain a very dangerous component or we can say that in other words that contain very toxic component which is called as or known as theobromine .

So as we see in the market , many types or many varieties of chocolates are available . 

So all in this chocolates , the more darker color of chocolates the more theobromine contains in it . And because of contain of more in amount of theobromine in chocolates it leads to be more harmful .

Here you may have one question on this topic is that " we eat chocolates but we still be fine , how is this possible ? " .

Yes my dear friend , you question is absolutely correct , but the reason behind this is , when we eat chocolates at that time our body instantly metabolize the theobromine component or we can say that in other words that our body quickly digest the theobromine component .

So therefore it is not very quite harmful for us .

So in case of dogs the process of metabolize of theobromine is much more slowly process. So therefore the theobromine component stay in their body for a longer period of time , and thus the theobromine leads resulting in vomiting , diarrhea , etc .

And moreover if larger amount or we can say that in other words that in larger quantity of ingested or eaten by the dog .

It leads or effects can be much more severe . So that the heart rate of the dogs might beat twice to it's normal rate , increasing the blood flow .

So these prove that , it is very dangerous for the dogs or we can say that in other words that it is very very lethal for the dogs .


So we hope you understand this concept clearly and nicely " Why dogs can't eat chocolates ? "



How Honey Bee make their honey ?

 How Honey Bee make their honey ?

                                               
SCIENTECHPLUS

Hello dear readers ,

Here in this blog post we will discuss more about on this topic , how Honey Bee make their honey ...?

This topic is quite going to be very interesting . Because in this concept some interesting fact hidden behind this .

So let's start about on this topic " How Honey Bee Make Their Honey " 

When we see the honey bee fill their honey comb with sweet honey , which hanging along the tree branches . 

We come into surprised and think , how they would be make honey by just sucking juice of flower . 

The question arises here because many big big industry , factories , small scale industry and large scale industry , etc. Does not make honey without taking help of Honey Bee .

So this is a big question and big fact of what is the secret fact behind this .

So to make honey the worker Honey Bee sucks sweet juice from flowers or we can say that in other words that nectar from flowers and stores this nectar in it's honey stomach .

After stores nectar from flower in it's honey stomach , the worker Honey Bee come back to the honeycomb / hive . 

After worker honey bee come to the honeycomb / hive it's vomit all the nectar which taking from flower to the processor honeybee's mouth .

So after taking processor Honey Bee nectar in it's mouth . So than the processor honey bee's in it's mouth and stomach one enzyme is produced which is called as invertase .

So these invertase added in nectar by the processor honey bee's in it's mouth and stomach .

So after added invertase in the nectar , the invertase breaks some amount of nectar into simple sugars like as glucose and fructose .

Than after happened these all processed than the processor honey bee's again vomit into another processor honey bee's mouth .

What is the work of another processor honey bee ?

The another processor Honey Bee added more invertase for breakdown more amount of nectar into simple sugar .

So these processed happened until most of  the nectar breakdown or converted into simple sugar .

So after happened all the processes of breakdown of nectar into simple sugar ,than the mixture of simple sugar is store or collected in the honeycomb .

So at this time ,the mixture is still watery in state . So to evaporates the water , Bees flap with their wing and thickens the mixture finally honey .


So we hope you understand this concept clearly and nicely " How Honey Bee make their honey " .




Monday 7 December 2020

Elephant's ears are so big , why ?

 Elephant's ears are so big , why ?

                                           
SCIENTECHPLUS

Hello dear readers ! do you ever think why do elephant ears is so big or large ? I hope you also think and this type of question is also come into your mind sometime . 

* So let's know more detail in simply and precisely

First of all to understanding this concept , we have to think for human being means think about our self . It means that , when you do whatever activities or perform any type of action .

So generally when we perform any actions , our body temperature goes high or our body become hot . 

So for maintain the body temperature or hotness of the body , our body produces sweat by the sweat glands . The producing of sweat by the sweat gland is happen naturally by our body , when it feels the temperature of the body goes high or become too hot .

So here in elephant , the body of elephant size is too large as compared to other living being on the earth . 

So you think here , according to the size of the elephant body . How much heat it would be produces , in during performing any action or activities ? 


The answer is much more heat , it produces much more heat during performing their activities . So when this elephant body produces much more heat during performing their activities , so you think here how the elephant is bear so much heat ? 

As we think here in comparison between human body and elephant body heat . The elephant body heat is quite high .

So how the elephant body minimizing their body heat or temperature of the body . We have already know that , the only one way to minimizing the body heat is by the sweating process .

But here in case of this elephant , the producing of sweat is not possible . So that's why , this elephant minimizing their body temperature or body heat by their big-big ear . 

What they do ? Just flapling their ears and the extra body heat or body temperature starts releasing from their body .

So here one more question is arises that , what is actually inside in the elephant ears ? Or what is the specialty of these big ears of elephant ?

So let's know about this , In the inner side or inside of the elephant ears , we will find a web like network of tiny blood vessels . 

The skin of the elephant ears is quite thin , so the blood vessels is very close to the surface . 

So when the temperature or heat of the elephant blood is goes high to the temperature of the surrounding .

than for minimizing or balance the heat , so the elephant is just flapping the their ears and all the extra heat of the body releases from the body and elephant feels cool .

So we hope you understand this concept very clearly and nicely .


Wednesday 2 December 2020

Derive or expression for the angle of banking

 Derive or expression for the angle of banking

Ans : 

                               

SCIENTECHPLUS

So first of all , we will discuss about what is angle of banking

The angle of banking is that , the angle made or make by the surface of road with the horizontal surface of road is called as or known as angle of banking .

So let consider a vehicle of mass m is moving with speed v on a banked road , banked at an angle  (θ) as shown in the diagram .

So here let consider F be the frictional force between tyres of the vehicle and the road surface . So here let's learn , the forces acting on the vehicle is ,

i) The weight mg acting vertically downward.

ii) The normal reaction N in the upward direction through C.G .


Here the frictional force in between tyres of the vehicle and the road surface can be resolved by into the, 

F (cosθ)  --  along horizontal direction

F (sinθ)  --  along vertically downward direction .


iii) The normal reaction N can be resolved into two components : 

a) N (cosθ) along vertical direction .

b) N (sinθ) along horizontal direction .


iv) The component N cosθ balances or equalises the weight mg of the vehicle and component F sinθ of the frictional force .

Therefore  N cosθ = mg + F (sinθ)

Therefore  N cosθ  - F sinθ = mg--------(consider equation 1) .


v) The horizontal component N sinθ along with the component F cosθ of frictional forces provides the necessary centripetal force  mv^2 / r .

Therefore   N sinθ + F cosθ = mv^2 / r   ----------(consider equation 2) .


vi) So dividing the equation (2) by (1) ,

SCIENTECHPLUS

So the magnitude of the frictional force depends on the speed of vehicle for a given road surface and tyres of the vehicle .

vii) Let we consider Vmax be the maximum speed of vehicle , and the frictional force produced at this speed given as ,

SCIENTECHPLUS

Now dividing the numerator and denominator of equation (5) by N cosθ , we have ,SCIENTECHPLUSSCIENTECHPLUSSCIENTECHPLUSSCIENTECHPLUS

viii) For a curved horizontal road θ0° , therefore equation (6) becomes ,SCIENTECHPLUS

ix) Comparing equation (6) and (7) it is concluded that maximum safe speed of vehicle on a banked road is greater than that of curved horizontal road or level road .

x) If Î¼ = 0  , then equation (7) becomes ,

SCIENTECHPLUS






So at this speed , the frictional force is not needed to provided necessary centripetal force . So therefore will be a little wear and tear of tyres , if vehicle is driven at this speed on the banked road , v (not) is called as optimum speed , 

xi) From the equation (8) as we write , 

SCIENTECHPLUS








 xii) Here the equation (9) represents angle of banking of a banked road . Formula for angle of banking does not require mass of vehicle m . Hence angle of banking is independent of mass of the vehicle .

So we hope you understand this derivation of angle of banking with clearly and nicely !




Tuesday 1 December 2020

Define and explain centrifugal or pseudo force

Define and explain centrifugal or pseudo force

Ans :
                                                         
SCIENTECHPLUS

Hello dear friends , did you know that , what is centrifugal force ? .

So let's know about and define this , 

Centrifugal force : The force acting on a particle performing uniform circular motion (U.C.M) which is along the radius and directed away from centre of circle is called as or known as centrifugal force .

The magnitude of centrifugal force is same as that of centripetal force , but it act in a opposite direction . 

So let's learn in detail about this centrifugal force

i) The uniform circular motion (U.C.M) is an accelerated motion . Therefore , when a particle performing uniform circular motion (U.C.M) is in an accelerated ( non-inertial ) frame of reference .

ii) In the non-inertial frame of reference , an imaginary force or we can say that in other words that pseudo force is to be considered in order to apply Newton's laws of motion .

iii) The magnitude of this pseudo force or we can say that in other words that centrifugal force , is same as that of centripetal force , but its direction is opposite to that of centripetal force . Therefore , this pseudo force is called as or known as centrifugal force .

iv) Let consider m is the mass of the particle performing uniform circular motion (U.C.M) , than centrifugal force experienced by the body is given by , 

F (CF)  =  mv^2 / r

But  v  =  rw  

Therefore  F (CF)  =  mrw^2


v) In the vector form ,

F (CF)  =  mw^2 r

Therefore  F (CF)  =  mv^2 ro / r

Where as  ro = unit vector in the direction of r .



* So here you think , why we called centrifugal force is called as or known as pseudo force ,

So let's learn more about this concept in simple in manner : 

a) The centrifugal force , whose origin is not defined due to the known natural interaction is called as pseudo force or we can say that centrifugal force .

b) Here the known natural interaction are like as , gravitational force , electromagnetic force , nuclear force , frictional force , etc these are the known natural interaction of this pseudo force or we can say that centrifugal force .

c) The Centrifugal force or we can say that pseudo force is directed opposite to the direction of accelerated frame of reference .

d) The centrifugal force or we can say that pseudo force is a fictitious force , which arises due to the acceleration of the frame of reference . Therefore , it is called as or known as pseudo force .


* Let's we will discuss about application of centrifugal force in our day to day routine life .

i) So here we take a first example , when a bus in motion or in a movement takes a sudden turn towards left , the passenger in the bus experience an outward push to the right . This is due to happen by the centrifugal force acting on the passenger .

ii) So let's take a second example , a bucket full of water is rotated in a vertical circle at a particular speed , so that the water does not fall . This is because of , weight of water is balanced by centrifugal force acting on it .

iii) So here we take the third example of this centrifugal force , the children sitting in merry-go-round experience an outward pull as merry-go-round rotates about it's vertical axis. This is due to happen by the centrifugal force acting on the children .

iv) So here we take fourth example on the centrifugal force , a coin kept slightly away from the axis of rotation of turn table moves away from the axis of rotation as the speed (acceleration) of rotation of turn table increases or rises . This is due to centrifugal force acting on it .

v) The bulging of earth at the equator and flattening at the poles is due to centrifugal force acting on it .

vi) The drier in washing machine consist of a cylindrical vessel with perforated walls . As the cylindrical vessel is rotating fast , centrifugal or pseudo force acts on wet clothes . 

This centrifugal force , out water through perforations thereby drying wet cloth quickly .

vii) The centrifuge works on the principle of centrifugal force or we can say that pseudo force . In the centrifuge , a test tube containing liquid , along with suspended particle is whirled in a horizontal circle . The denser particles are acted upon by the centrifugal force , hence they get accumulated at bottom which is on outside while rotating .

So we hope you understand this concept or phenomena of centrifugal force or we can say that pseudo force well n well .

Sunday 29 November 2020

The unit and measurement | physics


Here in this blog content , we will go to learn more about this unit and measurement .

So before we learn about unit and measurement , let's talk about field of measurement .

1) Physics 

2) physical quantity

3) units

4) Measurement 

So here , let's know about this given concept one by one .

1) Physics : The physics defined as , it is the branch of science , which deals with study of matter and natural phenomena .

2) Physical quantity : The physical quantities defined as , the quantity which are included in the physics is called as or known as physical quantities .

For an example : i) Length , ii) Mass , iii) Time , iv) Temperature , v) Velocity , etc.

3) Unit : The unit is defined as , the standard which are used for measurement purpose of physical quantities is called as or known as unit .

 4) Measurement : The measurement is defined as , the comparison of unknown quantity with respect respect to fixed quantity is called as or known as measurement . 

So let's known about , what is the requirement of unit ?

i) The first requirement of unit is , it should be universally accepted .

ii) The second requirement of unit is , it should be invariable with time and place .

iii) The third requirement of unit is , it should be well define .

iv) The fifth requirement of unit is , it should not be too large or too small .

v) The sixth requirement of unit is , it should be reproducible .

vi) The seventh requirement of unit is , it should be easily convert into smaller unit .


* Let's know about ,

a) Fundamental quantities : So the fundamental quantities is defined as , the quantity , which does not depends on any other quantities for their measurement is called as or known as fundamental quantities .

b) Fundamental unit : The fundamental unit is defined as , the unit of fundamental quantity is called as or known as fundamental unit .

What are the seven fundamental quantities ?

Fundamental quantities     Fundamental unit

1) Length                                    m ( metre ) 

2) Mass                                        kg ( kilogram )

3) Time                                        s ( second ) 

4) Temperature                         k ( kelvin ) 

5) Electric current                     A ( ampere )

6) Luminous intensity              cd ( candela )

7) Amount of substance           mole


                        

c) Derived quantity : The derived quantity is defined as , the quantity which depends upon one or more fundamental quantities is called as or known as derived quantity .

d) Derived unit : The derived unit is defined as , the unit of derived quantity is called as or known as derived unit .

So let's see the example of this derived quantities .

Derived quantity                 Derived unit

1) Area                                        m^2

2) Volume                                   m^3

3) Velocity                                   m/s

4) Acceleration                           m/s^2

5) Speed                                       m/s

6) Pressure                               N/m^2 or pascal

7) Impulse                         N.s (newton second)

8) Momentum                         kg . m/s

9) Stress                                    N/m^2

10) Strain                               strain has no unit

11) Frequency                         hertz ( Hz )

12) work                           kg . m^2/s^2  or joule

13) Power                          watt or joule/second

   etc...          


* What is systems of unit ? 

Ans : A set of fundamental unit and derived unit is called as or known as system of unit .

There are units are available in different groups . The system of units , which are used in C.G.S , M.K.S , F.P.S , and S.I . Here length mass and time are taken as basic physical quantities , using these basic quantities many physical quantities are derived .

1) C.G.S : Here in this C.G.S system , the unit length , mass and time are take as centimetre , gram and second respectively .

2) M.K.S : Here in this M.K.S system , the unit length , mass and time are taken as metre kilogram and second respectively .

3) F.P.S ( British system ) : Here in this F.P.S system , the unit length , mass and time are taken as foot pound and second .

4) S.I : Here in this , the S.I it is the abbreviation of international system of unit.


* So here , let's know about rules to write the unit ,

1) The unit name after scientist are not written with a capital letter .

For an example :

Right this one --  i) newton , ii) henry , iii) watt , etc.

Not right this one -- i) Newton , ii) Henry , iii) Watt , etc.

2) The symbol of unit name after scientist should be written in capital .

For an example : i) N - for newton , ii) H - for henry , iii) W - watt , etc.

3) Small letters are used as symbol for unit .

For an example : i) kilogram - kg , ii) metre - m

4) There is no full-stop or any punctuation mark should be used before or after the symbol of unit .

For an example :

Not right -- i) 40 m;   ii) 40.m   iii) 40m.

Right this one -- i) 40 m ii) 40 m  iii) 40 m

And last one is ,

5) The symbol of unit is always written in singular form .

For an example :

Right this one -- i) 1kg   ii) 10kg

Not right --     1kgs  ii) 10kgs


* So let's see the significant figures ,

The digit from ( 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 ) which are useful for assigning a true value to result is called as or known as significant figure .

So we learn ' Rules to write this significant figures '

1) So here in this all the digit from ( 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 ) are significant figures .

2) The second ones is , the zero become significant , if it comes in between two non-zero digits .

For an example : i) 102 km   ii 101 litre water

3) In the third rule , the all zero to the right side of decimal point and left side zero digit are non-significant .

For an example : i) 0.0123 -- 3 significant  figure

4) In the fourth rule , the zero is significant , if it is to the right side of non-zero digit after decimal point .

For an example : 0.2300 --. 4 significant figure

5) And in the fifth rule , if zero is in right side of the non-zero number than it may be significant or may be not .

For an example : i) 0.00476  -- 3 significant figure

ii) 1.024  -- 4 significant


* So let's learn about , what is an error ,

Error : So an error is define as , a fault or mistake can be observed even after most careful observation are taken for measurement is called as or known as error.

So here we will go to learn about the different types of error ,

1) Instrumentation error : In instrumentation an error causes due to faulty instrument is called as or known as instrumental error . 

So how we can fix this type of an instrumentation error ?

Ans : we actually fix this type of instrumentation error , by replacing faulty instrument with another instrument .


2) Systematic error : Systematic type an error cause due to faulty setting by the observer or an experiment is called as or known as systematic error .

So how we can fix this type of an error ?

Ans : So we can fix this systematic error or minimize this systematic error by identifying it's causes .


3) Random error : Random type an error causes due to climatic condition and human limitation is called as or known as random error .

So how we can fix this type of Random error?

Ans : We fix this Random error or minimize this Random error , by performing multiple time of an experiment and taking large number of reading . So that we can fix or minimize this type of an error .


Saturday 28 November 2020

The advantage and disadvantage of indoor antenna amplifier

 The advantage and disadvantage of indoor antenna amplifier

Ans. 

                                                     

SCIENTECHPLUS

So here in this blog content , first of all we will go to learn more about , what is indoor antenna ? . So the answer is , the indoor antenna is one type of antenna which receive t.v signal , but in this , it is actually place inside in the house and not place or mounted on the roof of house .

So we hope you understand , what is indoor antenna simply !

This indoor antenna is usually think about a very simple and inexpensive solution that may run well , when the receiver is close by to the transmitter . It's mean that , when receiver side and transmitter side relatively close to each other , than it's possible to transmitter and receiver do their work properly .

Instead of this , if both are shifted to a far distance , than it is loses it's frequency and it is failed to receive the signal . And will we no longer to watch the t.v channels .

So let's discuss about it's advantage and disadvantage .

First we take Advantage of indoor antenna amplifier

1) The indoor antenna amplifier is affordable : This indoor antenna amplifier is first of all free . We can install this indoor antenna amplifier by our-self , we did not pay any annual payment fees , as like as we pay fees for cable and satellite in annual payment antenna .

2) The indoor antenna is adaptable : Here the second advantage of this indoor antenna amplifier is more adaptable . It means that we can place in any where in our home , without taking much more tension . We simply place this indoor antenna amplifier on the t.v also .

3) The indoor antenna is work well in both rural and urban areas : As we see this , indoor antenna amplifier it's size is small as compared to roof antenna , so it's easily available everywhere . And also work with great potency .



Now , we will go to see the Disadvantage of this indoor antenna amplifier

1) In indoor antenna amplifier has very less channel choice option : In this indoor antenna amplifier , we sadly say that , if you are going to install this indoor antenna amplifier , than you have to accept this limited t.v channel choice option .

We can access number of channel in this indoor antenna amplifier , but if we talk about cable and satellite networks , it's provide our user far more t.v channel choice option .

2) The second most disadvantage of this indoor antenna amplifier is susceptible to interference : So here in this disadvantage , in the indoor antenna amplifier is , when transmitter transmit it's signal frequency the walls and ceiling of the house do not permit the signal to make allow to go to the receiver point.

Or we can say that in other words that , it weakens the signal frequency to go to the receiver side .

So because of this issue , the broadcaster needs high frequency for transmitting signal to the receiver side .




Friday 27 November 2020

The Circular Motion

 The Circular Motion

                                                    
SCIENTECHPLUS

So in this blog content we will learn about circular motion . So first of all we will know , what is circular motion ? 

So the answer is : the motion of a particle , which move along the circumference of a circle is called as or known as circular motion .

For an example of this , circular motion :         1) The movement of the the cyclist in a circular path , it is the best example of this circular motion .

So we will see some related example of these circular motion .

2) The motion of the planets around or circling the sun. 

3) The motion of the moon , around the planet earth .

4) Motion of the earth , around the sun .

5) The motion of the electrons , around the nucleus in an atom .

etc...

The name of circular motion or we can say that in other words that , Angular motion .

As we see the circular motion ,

So let's know about , what is actually mean of word motion

Ans : The mean of the word " motion " is , if a body or object change it's position with respect to time period , than it is called as or known as motion .

So for an example : 1) Hands of clock , 2) Moving fan , etc. 

The opposite of this motion is rest .

So we let's know about , what is rest ?

Ans : The mean of concept or phenomena " rest " is , if a body does not change it's position with respect to time period , than it is called as or known as rest .

So for an example : 1) A book is place on the table , 2) A chalk is in box , etc.

So let's see some definition as given as ,

1) Linear motion : The linear motion is defined as , when a body is moving along a straight line , than it is called as or known as linear motion .

2) Inertia : The inertia is defined as , the every body has a tendency , it does not change it's position by itself , unless and until external force is act on it , is called as or known as inertia .

3) Velocity : The velocity is defined as , the rate of change of displacement with respect to time , is called as or known as velocity .

4) Speed : The speed is defined as , the rate of change of distance with respect to time , is called as or known as speed .

5) Acceleration : The acceleration is defined as , the rate of change of velocity with respect to time , is called as or known as acceleration .

6) Retardation : The retardation is defined as , the negative of acceleration , is called as or known as retardation .

7) Gravitational acceleration or Acceleration due to gravity : Gravitational acceleration or Acceleration due to gravity is defined as , there is force of attraction between any body and earth , this force of attraction cause an acceleration , which is called as or known as gravitational acceleration or acceleration due to gravity .

8) Periodic motion : The periodic motion is defined as , the motion of a body , which repeated a position by itself in equal interval of time , is called as or known as periodic motion .

So let's see the examples of this Periodic motion : 1) Hands of clock , 2) A swing in a motion , 3) The motion of fan , etc .

So here let's see types of periodic motion ,

i) Oscillatory motion : The oscillatory motion is defined as , it is the motion , in which an object repeated the same motion again an again , is called as or known as oscillatory motion .

The example of this , oscillatory motion is : 1) vibration of tuning fork

2) Hands of clock 

3) The movement of swing 

4) The movement of simple pendulum

5) The compound bar pendulum

6) The moving fan 

etc...


ii) Vibratory motion : The vibratory motion is defined as , the motion in which , the body or object moves to and fro from it's mean position , is called as or known as vibratory motion .

The examples of this vibratory motion is : 1) The pulsating ( The doctor check pulse ) 

2) The vibration of tuning fork

3) The pendulum

etc...


iii) Simple Harmonic Motion ( S.H.M ) : The simple harmonic motion is defined as , it is the periodic motion , in which force is always directed towards the mean position and it's magnitude is directly proportional to the displacement of the particle , that is f is directly proportional to x , is called as or known as simple harmonic motion .

Or

We can defined simple harmonic motion in other words that , when an object or body moving to and fro along the same path , than it called as or known as simple harmonic motion .

Where as  f = force constant

x = displacement

Examples of this simple harmonic motion is : 1) The needle of sewing machine , when you see needle of sewing machine , it is constantly move in a same path to and fro .

So we will see some terms related to this simple harmonic motion is as ,

i) Time period or periodic time ( T ) : The time period or periodic time is defined as , the time required to complete one oscillation is called as or known as time period or periodic time . It's unit be second ( S ) .

ii) Amplitude : The amplitude is defined as , the maximum displacement of a wave is called as or known as amplitude . It's unit be metre ( m ) .

iii) Frequency : The frequency is defined as , the number of vibration are completed in one seconds is called as or known as frequency . It's unit be hertz ( Hz ) .

iv) Phase : The phase is defined as , it is the starting position is called as or known as phase . It unit is radian or degree .

v) wavelength : The wavelength is defined as , the distance between two successive crest or trough is called as or known as wavelength . It unit is Angstrom .

                



Thursday 26 November 2020

The Active and Passive components of electrical and electronics

 The Active and Passive component / element in Electrical & Electronics 

Here , if you see this word Active and Passive do you know that , what is the mean in electrical and electronics .

So let's first of all we learn to know that the , what is Active component / element in electrical and electronics ?

Active component / element : so , the active component or we can say that active element is capable of providing the energy independently for an infinite period of time , is called as or known as Active component / element .

                                             

SCIENTECHPLUS







SCIENTECHPLUS



Or 

we can defined Active component / element in other words that : the Active component or Active element is capable to provide an average power to some external device or we can say they electronic circuit , over an infinite period of time .

So take an example of this Active component / element : Battery , vacuum tube , voltage Source , Current Source , Transistor , Op-amp etc.


Passive component / element : so here , the passive component or we can say that in other words that , the passive element is not capable to providing the energy independently for an infinite period of time , is called as or known as passive component / element .

                                                    

Or

 we can define this Passive component / element : so in other words the passive component / element is define as , it is not capable to providing the energy independently for an infinite period of time , is called as or known as Active component / element .

So here in this Passive component / element we see the  examples of this is , Resistor , Capacitor , Inductor , Transformer , Diode , etc .

Let's see one by one concept of this passive component / element .

1) Resistor : As we know that , the Resistor is used to limiting the flow of electric current in the conductor , so as you know that it is only purpose of controlling the electric current only and it is not come in use to delivering energy independently for an infinite period of time .

                                                    

SCIENTECHPLUS

So the Resistor is energy dependent component or we can say that in other words that , it is energy dependent element .

2) Capacitor : so here as you know that , capacitor only store energy and releases energy when come in use . 

So here in this capacitor also you see that it is a energy dependent component or we can say that , energy dependent element .

                                                      

SCIENTECHPLUS

                                                           

3) Inductor : We know that about inductor , which it is a passive component / element which is very capable to storing the electrical energy in the form of magnetic energy .

So here we see in this inductor also , if we cut supply of electrical energy it stop storing energy in the form of magnetic energy . So it is also a energy dependent component or we can say they , energy dependent element .

                                                     

SCIENTECHPLUS

4) Transformer : The transformer work to " step-up " or " step-down " voltages and current . But frequency remain as it is or we can say that frequency remains constant .

But transformer also fail , if we cut off the supply source of voltage and current . Than it means that , these also is energy dependent component or we can say that energy dependent element .

                                          

SCIENTECHPLUS

5) Diode : So as above given those component or element , this diode also work when supply sources of voltage and current is connected . So here , this diode is make flow of current in unidirectional of alternate current ( A.C ) .

So simply it's mean that , these diode is also energy dependent component or we can say that in other words that , energy dependent element .

                                                 
                                                      

SCIENTECHPLUS


Tuesday 24 November 2020

The Stress Management | physics

Do you know this , what is stress management ? , Here the answer is stress management , simply means that to control or we can say that to manage of our mentality , emotion , thoughts etc. is known as or called as stress management .

So here let's start to know in detail all about stress management . We have all today seen that in hurly-burlies  life , we have not time to eat our meal . We have not a bit of second to think about our self . So we hope you may think that , how busy we are in today's life .

As we busy in today's life , we slowly slowly become careless of about our health . So because of our carelessness , we fall ill physically and mentally . So when this type of problem happen in the life of people , then they got tremendous pain in her life . So you can imagine , how painful situation created at that moment .

So many people choose option to move towards taking smoke , alcohol , drugs as like intoxicant substance for minimising our pain . Or we can say like that they want to  forgetting about our painful life and they wanted free stressful life . But you think here is it a wrong or right option ? .

So the option is absolutely wrong , so here you may ask , why it is wrong ? , So the answer is , for understanding this concepts you may have to think like , when you are in a stressful situation , what is going with you ! In that situation your mind keep constantly generated uncontrollable thoughts . Which it proves very lethal for your health and it leads to several health and mental problems.

So , the right option to care your self without taking any kind of intoxicant substances . Which is really realy very bad for your health and mental problem . So here the right option is laughing , you may be heard from somewhere " laughing is the best medicine " .

So have you seen the loudly laughing people ( citizen ) in the morning in public garden !! , it is really popularized by the name called       ' laughter club ' . So here in this ' laughter club ' people gather and talk to each other and share our feeling to each other .

As you know that " sharing is caring " it means that 'when you have problem and if you discuss with your friend partner the pain automatically goes down ' which is really it proves that " sharing is caring " .

So when you feel alone yourself , you simply talk to someone , then you really feel very peaceful in your mind and slowly slowly you come to in relax position . This concept is really work , and remember always whenever you feel some kind of unwell or we can say that in other words , when you realize yourself , I am not feeling well or when you stuck in such a big problem you have apply this concept to over come out to that type of situation . 

You have many ways of expression like establishing communication with your parents , friends , cousins , teachers , peers , native relatives and many more option you have to expressing your feeling to your near and dear ones , which it is really really help to minimizing of your stress .

Instead of sitting alone , you have many several option to do , when you are in a stressful situation . For example , like such as drawing , painting , listening Favourite music , watch comedy shows , spend time in nature , make a photography album , dancing , go for walking in a morning , walk on green grass in the early morning , etc. this are very helpful to minimizing of your stress. 

So you have must properly use your free time . By doing this types of activities with yourself . When you doing this type of activities , your mind get diverted and you stop think about negative thoughts . By involving your self in this types of activities , the negative thoughts automatically get vanished .


1 ) So overcome to that type of problem, you have to simply start meditation for 10 minutes . And slowly slowly practice to increasing time period for meditation . 

2) You may heard from some where, laughing is the best medicine . So in the early morning try to laugh loudly by open your hands in the sky .

3) Take a proper sleep dose to feel fresh and relax . A good sleep dose leads to peace in the mind .

4) Try to sleep early and try to wake up early in the morning , than you feel peace in mind. The reason wake up early in the morning is that , in the early morning time everywhere in our environment  silence zone is created . Which is very best moment for us to take the full advantage of that moment .

5) After wake up early in the morning you should drink lukewarm water . Which is very best for our stomach . It cleans our complete digestive system .

6) So by follow this tips you can managed your stressful situation . Whatever problem comes in you life , you fully ready to face that type of challenge , without any losing self confidence . You confidently face that type of situation with your self esteem .

       

Sunday 22 November 2020

The - CPH4

 The - CPH4


Here , in this blog you get the complete detail about the CPH4 . The CPH4 stands for 6 - carboxytetrahydropterin synthase , this is the real name of the CPH4 or we can say that IUPAC name, means that ( International of pure and Applied Chemistry ) .

                 The CPH4 play a very vital role or we can say that play a very significant role in the function of small organisms cell . The enzymes in the cell are used to produce other types of vital molecules that are very essential for the cell to functioning properly. The CPH4 enzyme produces Queuosine . The Queuosine is a molecule that are very essentially helps to hold the tRNA of the bacterial cells together . It is just like glue to stick or we can say in other words that, it binds to each other .

                So here before getting into much detail concept , let me get you familiar with some terminologies . This is literally all about nootropics . Nootropics are those substances ( Matter ) , which enhance cognition , memory and thus it's facilitates in learning .The CPH4 are still a subject of research and aren't still classify into any types of category of drug . 

                The effects of these nootropics depends strongly upon the neurochemistry of each person . So it means that , different-different person have different-different neurochemistry accordingly . So here in these ' Lucy ' movie scarlet Johnson takes a drug called CPH4 to approach her brain function and because of this , she becomes the most intelligent and powerful human being in the whole planet .

                 Now CPH4 is a pure work for fiction as like as NZT drug . The NZT drug that Bradly Cooper takes in the movie 'Limitless'. Both these drugs are actually approach the brain to the point , where the subjects can use all of their gray matter on a regular basis and because of this , nothing can stop them . What most people do not aware about that both these CPH4 and NZT were inspired by a real life medication called as modafinil .

                So let's learn more about these modafinil . Unlike it is a fictional version , modafinil do not allow access to gray matter but it improves the cognitive function and memory . Modafinil stimulate the brain and subject enter a state of wakefulness , alert , aware and in this way , it is easier to focus on a different activities without experiencing much for .

              The best part of this is that , it has not got any side effects , so it is safer to take it without rising addiction stuffs . So we can say that , it is actually possible to dream of a time , where pills like CPH4 will be available for public , but for the time being condition , modafinil is a great recommended option analogical to CPH4 .

             The CPH4 produces in a pregnant women in a six weeks of pregnancy . These biological molecule produces during six weeks of pregnancy in a very small quantity. But the real fact that of this CPH4 , when we consume this we attain full capacity of our brain is totally wrong . You also think like , if we attain our full capacity of our brain , it is possible that whatever inside of our body organs which is functioning without our control , it is self functioning organs . It is possible we can run properly , the answer is absolutely no ! .

                 Take for example : Let's say if we got full capacity of our brain power to use , it is possible for us in 24 times 7 to function of our whole system properly . We do not got any time for other activities in 24 hour . We busy to run our body system in 24 hours , isn't ?.



             

Wednesday 18 November 2020

What is the artificial intelligence (A.I )

What is Artificial Intelligence (A.I )

Ans. 
                                                        
SCIENTECHPLUS


First of all we are talking about , what is artificial intelligence  ( A.I ) ?
        So , artificial intelligence is a simulation of human intelligence in a machine that are programmed like to think according like a human being and mimic their action accordingly . Or we can say that , it is upcoming new science technology which give new rising of human being for their making daily life routine quite easier and comfortable .
              Artificial intelligence technology is programmed like as , it can able to take self decision to solving a problem . 
               If you want to know that in a very simple manner than you think or we can say that you imagine as like , whatever intelligence activities of human being the same activities are perform by this Artificial Intelligence ( A.I ) or you can say act by this Artificial Intelligence  ( A.I ) .
              Artificial Intelligence  ( A.I ) is giving a boost to the boundaries of the machine to enabled it's functionalities . This gives dynamical innovation to this technology facilitates machine to perform with a degree of autonomy .

               The following given is a primary advantages of the Artificial Intelligence (A.I)

1) Because of Artificial Intelligence Reduction in Human error : 
           The term " Human error " was arise because human being make mistakes so much in time to time . But if you talk about computer or a machine however , do not make these mistakes if they are programmed properly .  
            As we talk about Artificial Intelligence  ( A.I ) . the artificial intelligence , the decision are taken from the previously stored information applying a certain set of algorithms . So that , error are reduced and chance of getting accuracy with a greater degree of precision in a possibility .
        
2) Artificial Intelligence takes the risks instead of Humans :
              This is the biggest advantages of this Artificial Intelligence ( A.I ) . We are able to overcome to many risky limitation of Human by developing an Artificial Intelligence ( A.I ) . 
            So let's understand this concept with one example, we take help of robots in the protection security of country boundaries . So if any damages or fault happen during shooting , bombarding in the war , it is very easily to recoverable, But if we talk about Human Being in place of robot than it is quite harder to controlled the life of the army .
            So here , for security purpose Robot take risks more than the limitation of Human Being .

3) The Artificial Intelligence are available 24 times 7 :
            As you know that Machine are very efficiently work for a longer period of time without getting tired . But in case of our's Human Being it is not possible to work that much of time .
             So here , Artificial Intelligence provides services 24 into 7 hours , without getting tired and leave . So this is the major role play by this Artificial Intelligence ( A.I ) .





  

Tuesday 17 November 2020

Explain working principle of negative clamper circuit

 Explain working principle of negative clamper circuit

Ans. 

                                          

SCIENTECHPLUS

   First of all we see , what is clamper circuit? , so the clamper circuit , which changes or we can say that shift direct current ( D.C )  signal to according to our desire level , without any changing the shape of the signal.

 So , here in this negative clamper circuit we go to learn it's working principle or we can say that in other words that , we go to learn it's operation of this negative clamper circuit. 

  So , here the negative clamper circuit consist of a diode , a resistor and a capacitor. The negative clamper circuit shifted the output ( O/P ) waveform signal to the negative portion when we give sinusoidal input ( I/P ) waveform signal .

    During Positive Half Cycle

                                  

So , during in a positive half cycle , the input ( I/P ) of this circuit is equal to ( Vm )  volt . And therefore the diode goes in forward biased condition . And if we consider , this diode is a ideal diode , than it is represented by the short circuit .

                                                               

SCIENTECHPLUS

                    And due to that , constructively this resistor will also get short circuited . So therefore , in during positive half cycle the capacitor will get charged through this path and this capacitor will get charged upto peak value of the voltage ( Vm ) . So therefore , during positive half cycle the output ( O/P ) voltage Vout will be equal to zero ( 0 ) .


   During Negative Half Cycle

                                             

So , during in a negative half cycle , the polarity of the input ( I/P ) voltage signal will get reversed . And now here , if you notice the voltage , which is appearing or we can say that come into existence across the diode is equal to ( - 2Vm ) . It's means that summation of these two  ( Vm ) voltages and therefore that this diode get in reversed biased condition , so that we can replace it with the open circuit.

                                                

SCIENTECHPLUS

             So , in during negative half cycle , the output ( O/P ) voltage ,

                       Vout = - Vm - Vm

                       Vout = - 2Vm

So , if you come see the overall output ( O/P ) waveform signal , than it will look like this , 

That's mean that ,the entire input ( I/P ) waveform signal , get shifted to a voltage of    - Vm . Now even though , the clamper circuit changes the direct current ( D.C ) level of the input ( I/P ) waveform signal , but here in  peak to peak voltage of the output ( O/P ) waveform signal is remain same as the given input waveform signal .

              So , here if you come to see , the input ( I/P ) waveform signal is varying from  ( Vm ) to ( - Vm ) . It's means that the peak to peak voltage of the waveform signal is equal to ( 2Vm ) . While in the output ( O/P ) the waveform signal is varying from ( 0 ) to (-2Vm) . It's means that , here also the peak to peak voltage is equal to ( 2Vm ) .

              So , in this way by using this negative clamper circuit , the Direct Current ( D.C ) level of the input ( I/P ) waveform signal can be shifted towards the negative side .

Sunday 15 November 2020

State the need of filters

 State the need of filters

Ans. 

                                                      

SCIENTECHPLUS

If we look for need of filters , than first of all we need to understand where do  filter is used ? 

       Filters is used in the rectifier bridge circuit or we can say that in other words that it is used in a rectifier bridge device .

            So , first of all let's see what is rectifier , rectifier is an electronic device or we can say that , rectifier is an electronics circuit which is used for converting  (A.C) voltage or (A.C) current into a unidirectional flow of pulsating (D.C) voltage or (D.C) current .

            As we know that rectifier bridge circuit gives output (O/P) pulsating direct current (D.C) but it is no more able to gives pure direct current . So because of this , we no more longer use in a some devices or we can say that some circuit because it may damage the circuit .

            So overcome to this problem , we used filters to get pure direct current output (O/P).

1) As we know that , rectifier bridge circuit are used to convert alternate current  (A.C) to direct current (D.C) but it not gives pure direct current so here filters play a very significant role to gives output pure direct current output .

2) Most advanced electronics system need pure direct current (D.C) supply to drive the electronics system .

3) To build a good power supply , which gives output pure direct current  (D.C) , we need to removed out alternate current (A.C) from the output rectifier bridge circuit or we can say that in other words that , we need to filtered out the alternate current (A.C) from the output (O/P) of the rectifier bridge circuit or we can say that rectifier bridge device .

4) Filters are the electronics device or we can say that , filters are the electronics circuit, which is used along with rectifier in order to get a pure ripple free direct current (D.C) .

5) Filters can connected with any type of rectifier bridge circuit or we can say that rectifier bridge device given as , Half wave rectifier bridge circuit (HWR) and Full wave rectifier bridge circuit (FWR) 

6) The filters circuit uses Resistor (R) , Capacitor (C) and Inductor (L) , That's why it is called as passive filters .

Saturday 14 November 2020

Explain working of half wave rectifier with the help of diagram & waveform

 Explain / Describe working of half wave bridge rectifier with the help of diagram & waveform

Ans. 

                                           

SCIENTECHPLUS



SCIENTECHPLUS



            

POSITIVE HALF CYCLE

If supply of positive half cycle to the circuit than the diode in the circuit start conducting in a forward biased condition . We know that diode start operating in a forward biased or we can say that start working in a forward biased . But not conducting or we can say that not start working in a reversed biased mode .

              So , here in this circuit when supply of positive half cycle is apply to the circuit then diode conducted in a forward biased and that's why it allow current to flow through the conductor along through Load Resistor ( RL ) .

            So , if we see the input (I/P) and output (O/P) wave signal than its look like is as , if we give positive half wave signal to this circuit than we will get output of this signal .

  

        Negative Half Cycle 

If supply of negative half cycle to the circuit than the diode in the circuit not start conducted or we can say that diode start conducted in a reversed biased mode condition . As we know that diode start operating in a forward biased mode condition or we can say that start working in a forward biased mode condition . But if we apply negative half wave cycle to this circuits than it's start operating in a reversed biased mode condition .

              So , here in this circuit when negative half wave cycle is apply to the circuit then diode not conducted in a forward biased mode condition and that's why it doesn't allow current to flow through the conductor along through Load Resistor (RL) .

           So , if we see the input (I/P) and output (O/P) wave signal than it's look like as , if we give negative half wave signal to this circuit than we will not get output of this signal .

                

            

        

Friday 13 November 2020

State the need of biasing of transistor

 State the need of biasing of transistor 

Ans. 

                                                       

SCIENTECHPLUS

To understanding the need of biasing of transistor , first of all we need to understand the term what is biasing ? 

          Biasing means to supply a power supply to the circuit or we can say that apply D.C or A.C signal to the given circuit for start operating .

              So , in electronics and in electricals all devices or we can say that all circuits are work or we can say that start operating only by supplying power supply .
              So like that, here transistor work in a biasing mode . A biasing is required to operate the transistor or we can say that to start working of the transistor . Without biasing , it is not more able to obtain an output ( O/P ) .

              A biasing is required to activate the transistor and prevents it to either saturation mode or cut-off mode . A biasing is a phenomenon or a concept of getting a proper D.C collector current at a certain D.C voltage by setting up a proper point .



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