I am not very good in maths and physics could I succeed in studying B-tech

* First of all, you have to think are you confident from inner-self ? to move ahead towards B-tech study.

* Are you interested to do this with patience, without taking any worry.

* It is not matter how much you weak in any subject, it is only matter about your choice of confidence in any stream.

* You have to not think like, I am not good in this subject. You have to think like, why I am wanting to go in B-tech study.

* What is main motive for me to doing B-tech.

* Think our-self, Can I only do this because of good package salary or just for high reputation.

* So my friends, its very simple to take decision about yourself.

just talk this worlds with yourself and think on it and then take any decision on it.

Application of elasticity | Physics

 1) while designed concrete or steel structure it is design to bear more load than actual load.

 2) To determine strength of material.

3) In engineering to determine tensile strength of different of different material.

4) The elasticity property has to be taken into account in the construction of building and fly over, bridges etc.

5) When we wind a watch its spring is strained and energy is stored in it as strained energy, the spring slowly rotates inside of the watch due to strain energy.

Defination of stress | Physics

* Ultimate stress: It is the maximum stress with which system is                                          capable of withstanding.

* Working stress: It is the actual load on the system.

* Breaking stress: It is the maximum stress at which wire will breaks.

* Factor of safety: It is the ratio of ultimate stress to working stress.

Difference between elastic body and Plastic body | Physics

                      Elastic body 

Definition: The property on account of which a body regain it's original size and shape on removal of external deforming force is called as elastic body.

Process:  It is reversible.

Ductility: It is less ductile in nature.

Modulus of elasticity: The ratio of stress to strain is low or equal.

Toughness: They have the ability to absorb energy up to fracture.

Bonds: The molecular bonds do not get fractured.

Shape and size: The shape and size does not change permanently.

Example: Rubber.

                               Plastic body

Plastic body: The property on account of which a body doesn't regain its original size and shape on removal of applied force is called as plastic body.

Process: it is irreversible

Ductility: They are highly ductile in nature.

Resilience: They have low yield strength.

Modulus of elasticity: The ratio of stress to strain is high.

Toughness: They do not have the ability to absorb energy up to a fracture.

Bonds: The molecular bonds are fractured.

Shape and size: The shape and size changes permanently.

Example: Plasticine

              

Explain Viva of Electrostatics | physics

1) What is electrostatics ?

Ans: It is the branch of science which deals with the study of electric charges and force between them.

2) Definition of electric charge 

Ans: It is the physical property of the matter that experience a force when it is place in electric field there are two types of electric charge. 

 i) Positive    charge (+ve)

 ii) Negative  charge  (-ve)

It is denoted by q and it's unit is coulomb (c)

3) Explain coulomb low of electrostatics or coulomb Inverse square low 

Statement: It states that the force of attraction or repulsion between two electric charges is directly proportional to the product of the two charges and inversely proportional to the square of the distance between them.

4) Definition of electric field.

Ans: The space around the electric charge is called as electric field.

5) Definition of electric flux density.

Ans: The total number of electric lines of force per unit Area is called as electric flux density. and it is denoted by (D).

6) Definition of Electric field intensity.

Ans: The force Acting Per unit charge is called as electric field intensity. It is denoted by (E).

7) Definition of Electric flux.

Ans: The total number of electric lines of force is called as electric flux. And it is denoted by ψ (Psi) it unit is coulomb.

8) Definition of electric potential.

Ans: The amount of work done in bringing a unit positive charge from the boundary of infinity to a given point against electric field is called as electric potential and it is denoted by (v).

9) Definition of absolute potential (v).

Ans: The amount of work done is bringing a unit positive charge at a given point is called as absolute potential.

10) Definition of electric potential between two points.

Ans: The amount of work done is bringing a unit positive from point R to points S is called as potential difference between two points.

List requirements of good servo motors.

 i) The linear relationship in between electrical control signal and the rotor speed over a wide range.

ii) The inertia of rotor should be as low as possible.

iii) A servo motor must stop running without any time delay, if control signal is removed.

iv) For low inertia, it is designed with large length to diameter ratio for rotors, compared to its frame size. The rotor of servomotor has very small diameter.

v) It's response should be as fast as possible, for quickly changing error signal, it must react with good response. This is attain by keeping torque to weight ratio high.

vi) It should be easily reversible. 

vii) It should have linear torque speed channel.

viii)  It's operation should be stable without any oscillation or overshoot.

State disadvantage of single mode optical fiber

 Ans:-

i) The laser required are costly and can be used with only one cable at a time.

ii) The dependency on laser it means that single mode cables are less versatile and more limited in their applications.

iii) Single mode solution are often more expensive to deploy and operate since laser based equipment generate more heat.

State advantage of WDM

 Ans:-

i) To use the full capacity of the fiber optic cable by allowing multiple beams of light at different frequencies on the same fiber    optic cable.

ii) Full duplex transmission is possible.

iii) Easier to reconfigure.

iv) Optical components are similar and more reliable.

v) This could be the best approach, as it is simple to implement.

vi) High security.

vii) Various optical channel can support different transmission formats.

3x^2-3 =5x solve this

 Ans:-

3x^2 - 3 = 5x 

Now we rearranging this expression ax2 + bx + c = 0 in that manner than we get,

3x^2 - 3 - 5x = 0

∴  3x^2 - 5x - 3 = 0

Now we solve this sum by quadratic formula,

1+1-12-12-67-972= What is the answer ?

 Ans:-

1+1-12-12-67-972 = ?

we solved this problem by golden formula of plus and minus

( +, - ). In this formula -1 -1 = -2, 

                                 ∴    -3 -3 = -6,

                                 ∴     1 + 1 = 2, 

                                 ∴     3 + 3 = 6

  ∴  1 + 1 - 12 - 12 - 67 - 972

         ↓                    ↓                   

         2                -1063    

                    

∴       2 - 1063 = 1061

This is our required Ans:- 1061

Find the product of place value and face value of 9 in the year of Independence.

 Ans:-

Year of Independence is 1947

so that, the face value of 9 in 1947 is = 9 

    ∴   the place value of 9 in 1947 is  = 900

Now the product of place value and face value of 9 in 1947 is = 9 × 900

                                                                                                     =  8100

The product of place value and face value of 9 in the year of Independence is = 8100

The ratio of the length of a rectangle to its width is 5:2. If the length of rectangle is 40 cm, what is its width​

 Ans:

Ratio of length and width of rectangle must be in proportion to the actual length and width of the rectangle.

Let we consider width of rectangle be = x

Given:-

Ratio of  Length : Width is = 5 : 2 respectively

Actual Length is = 40 cm

Now we know that, they are in proportion, so we can write them as,

5 : 2 = 40 : x

∴ 5/2 = 40/x

Cross multiplying, we get

5x = 80

x = 16 cm

Therefore width of rectangle is 16 cm.

Expand this expression (p+q²)²​

 (p + q²)²​ 

We solved this expression by this formula (a + b)² = a² + 2ab + b²

(p + q²)²​ = p² + 2pq² + q4

so this is our required Ans:- p² + 2pq² + q4

Hope you will find this answer helpful..!!

There are how many types of electronics in the world ?

If we talk about electronics in the world, than I think that there is no limitation, because every day there new-new features updates we listening isn't ?.

Actually we can't define the limitations of electronics in the world.

But in current times, the types of electronics is,

1. Digital electronics
2. Analogue electronics
3. Microelectronics
4. Circuit design
5. Integrated circuits
6. Power electronics
7. Optoelectronics
8. Semiconductor devices
9. Embedded systems
10. Audio electronics
11. Telecommunications
12. Nanoelectronics
13. Bioelectronics

How to upgrade window 10 home to window 10 pro for free !

 This is quite easy easy and simple tips to upgrade window 10 home to window 10 pro.

A) So first of all we need to uninstall window 10 home activation from our Pc/ Laptop.

B) Secondly to uninstall window 10 home from our Pc/ Laptop by using CMD.

C) Open CMD as an administrator and type command code.

This command code for uninstall window 10 home:

i] slmgr /upk  press Enter button.

ii] slmgr.vbs /cpky  press Enter button.

iii] slmgr /ckms  press Enter button.

iv] slmgr.vbs /ckms  press Enter button.

After applying this above command, you have to restart your PC/ Laptop. 

And again go in your PC/laptop search box and type CMD and open CMD as an administrator.

By using this command code your PC/ laptop upgrade from window 10 home to window 10 pro.

i] slmgr.vbs /ipk W269N-WFGWX-YVC9B-4J6C9-T83GX  press Enter button.

ii] slmgr.vbs /skms kms.teevee.asia  press Enter button.

iii] slmgr.vbs /ato  press Enter button.

Now your PC/Laptop successfully upgraded to window 10 pro.

Distinguish between ordinary and extra ordinary ray

Ans:

Ordinary rays

1) The ray's which obeys Snell's law and laws of refraction is called ordinary ray.

2) It is denoted by O.

3) It passes undeviated through the crystal.

4) Inside the crystal, speed of O-ray is less than E-ray.

5) The speed is constant in the medium.

6) It gives spherical wavefront.

Extra ordinary ray

1) The ray which does not obey the laws of refraction is called extra ordinary ray.

2) It is denoted by E.

3) It deviates after refraction.

4) Inside the crystal, speed of E-ray is more than O-ray.

5) The speed is not constant in the medium.

6) It gives ellipsoidal wavefront.

What is dichroism ?

 Ans:

1) The property by which some doubly refracting crystals absorb the ordinary rays (O-rays) completely and extraordinary rays whole direction is parallel to the optic axis passing through the crystal, is called dichroism.

2) The crystal possessing dichroism property is called dichroic crystal.

3) Dichroism substance produces linearly polarised light 

4) This property of substance is used to construct a Polaroid.

Example: Tourmaline crystal.

State the main uses of polaroids.

Ans: Uses of Polaroids:

 1) Polaroids are used in motor car head lights to remove head light glare.

2) Used in three dimensional movie cameras.

3) They are used to produce and analyse               polarised light. 

4) They are used as filter in photography. 

5)They are used in window of aeroplanes to control amount of light.

6)  Used in polarising sunglasses (goggles) to protect the eyes from glare of sunlight.

7) They are used to improve colour contrast in old oil paintings.

8) They are used in calculators, watches, monitors of laptops which have LCD screens.

State methods to produce plane polarised light

 Ans: 

a) Reflection 

b) Scattering

c) Refraction 

d) Property of dichroism in calcite or quartz materials.

e) Polaroids

Explain the terms: i) Plane polarised light ii) Plane of vibration iii) plane of polarisation

 Ans:

A) Plane polarised light: The light waves in which vibrations of the electric field vectors are confined only to one plane are called polarised light.

B) Plane of vibration: The plane in which the vibrations of polarised light take place is called as plane of vibration.

C) Plane of polarisation: The plane perpendicular to the plane of vibration in which there are no vibrations of polarised light is called as plane of polarisation.

Why animals are preserved in science laboratory are kept in glass jars not in steel jars?

Because: We can't see, if animals preserved in steel jar. But in case of glass jars we can easily see animals and birds, whatever living things in lab. Those all are kept in glass jars only.

Because of nicely study about particular animals or plant.

And one important thing is that, in wet specimen glass jar, the liquid in which organism are kept is formaldehyde. So formaldehyde is corrosive to carbon steel.

So therefore, steel is not taken in use for preserved organism in jar.

Tricks and tips for activation of window 10 pro free easily

 Hello guys, in this article I am going to tell you about few and simple tricks and tips on how you can easily activate your window 10 pro free easily.

1) First of all, in your PC/ Laptop you have to go in search box option and type CMD, then you have to open CMD as an administrator and open.

2) In CMD type this code : i)  slmgr.vbs /ipk W269N-WFGWX-YVC98B-4J6C9-T83GX   then press Enter button.

3) Second code : ii) slmgr.vbs /skms kms.teevee.asia  then press Enter button.

4) And last third code : iii) slmgr.vbs /ato  then press Enter button.

And now your window 10 pro is successfully activated.

But in some cases, you will find your window 10 pro is not activated by this code, so it means that some files or folder  corrupted in your PC/ Laptop.

So that's why your window 10 pro is not activated.

So in that case : 1) First you have to go in setting and in setting you will find update and security option and then you have to go in Recovery option, so in the Recovery option you have to select Reset option and then you have to Reset your PC/ Laptop Completely.

When you click on Reset option then it will show two option i) Keep files and folders ii) Remove files and folder everything  so you go in Remove files and Folder.

After completing of Resetting of Pc/ Laptop then you have to update your window 10 pro and then uses above Code in CMD.

It will 💯 fix your issues !!!

A train cross a tunnel in 20 seconds at the entry of the tunnel velocity is 72 km/hr and the exist of the tunnel 36 km/hr. Find the length of the tunnel.

Solution:-

  t = 20 second.

 u = 72 km/hr  =   72×1000 / 3600 

                    u =   20 m/s   

  v = 36 km/hr = 36×1000 / 3600

                   v  =   10m/s

  a =  v - u / t

     =  10 - 20 / 20

     = -10 / 20

   a   = - 0. 5 m/s² 

v²   =  u²  + 2as

S    =  v² - u² / 2a

      =  (10)²  - (20)²  / (2 ) × (- 0.5)

      =  100 - 400 / -1

      = -300 / -1

 S   = 300 m

                            ∴ The length of the tunnel is 300m.

State applications of connectors used in optical fiber communication

1) Optical fiber connectors are used to join optical fiber where a connect /disconnect capability is required.

2) Optical fiber connectors are used in telephone exchange for customer premises wiring and in outside plant applications to connect equipment and fiber-optical cables.

3) Outside plant application may require connectors be located underground or on outdoors walls or utility poles.

Compare p-i-n and avalanche photodetector

 Pin diode:- 

1)  PIN photodiode does not have a high intensity electric field region.

 2) sensitivity is very low in PIN photodiode.

Avalanche photodetector:- 

1) Avalanche photodetector is a high-intensity electric field region.

2) sensitivity is very high in Avalanche photodetector.

Give selection procedure of compensation.

1) In general there are two situation in which compensation is required.

2) In 1st case, the system is absolutely unstable & the compensation is required to stabilize, if as well as to achieve a specified performance.

3) In 2nd case the system is stable, but the compensation is required to obtain the desired performance.

4) The system which are type 2 or higher are usually absolutely unstable, for these type of system clearly load compensator increase the margin of stability.

5) In type 0, type 1 system stable operation is always possible, if the gain if sufficiently reduced. In Such cases any of the 3 compensator lead, lag and Lead lag may be used to obtained the desired performance.

Compare lead and lag compensator

 Lead compensator   

1) Introduce lead phase shift in the system

2) Improve transient response

3) Decrease rise time 

4) Decrease settling time 

5) Increase Bandwidth

6) Faster response

7) less overshoot

8) Increasing damping

Lag compensator 

1) Introduce lag phase shift in the system

2) Improve steady state response

3) Increase rise time. 

4) Increase settling time.

5) Decrease Bandwidth 

6) Slow response 

7) Increase overshoot.

8) Decrease damping

State function of switches in optical fiber link.

  

1) An optical switch is a device that selectively switches optical signals from one channel to another.

2) In commercial terms it refer to any piece of circuit switching equipment between fibers.

3) The switches are used to switch the traffic stream from primary fiber into another fiber in case the primary fiber fails.

What is the function of OTDR

 i) OTDR detects faults going in the optical fiber       link.

 ii) Fast automatic testing.

 iii) Troubleshoot the faults in optical fiber                   communication.

iv) Maintain optical telecommunication network.

Requirements of rectifiers

Rectifier is a electronic circuit or a device which is used for converting AC voltage/current to DC voltage/current.

Requirements of rectifiers:- i) Rectifier is able to convert two directional Alternate Current (AC) to unidirectional pulsating Direct Current (DC).

ii) Rectifier removes, the negative part from Alternate Current (AC).

iii) By using Rectifier and step-down transformer we get desired DC voltage.

iv) Rectifier divided into two types:-  a) Half wave rectifier

                                                    b) Full wave rectifier

State concept of GPON

 

GPON or Gigabit passive optical network is a point to multipoint access mechanism.

The main characteristics of GPON is the use of passive splitters, which enable a single feeding fiber from the networks provider's central location to serve multiple users with their homes and small business. 

GPON uses the advanced Encryption standard (AES) for security purpose, which was designed to be efficient in both hardware and software and support a block length of 128 bits and key length 128, 192 and 256 bits.

GPON also support all types of Ethernet protocol.

Describe DWDM development of multiple wavelength with the help of a neat diagram. State its advantages also

Fig shows DWDM deployment on an OC-192 trunk ring for wavelength.

DWDM is a technology that puts together multiplexes data signals from different sources so, they can share a single optical fiber pair while maintaining complete partition of the data stream.

Individual signal is carried on a separate light wavelength. The dense part of DWDM refers to the fact that more than 80 separate wavelength, each about 0.8 of a nano-meter (nm) wide can short a single optical fiber.

DWDM allows enormous amount of data to traverse a single network link. Because they are

carried an clear wavelength, the streams also called channel do not interfere with each other.

Consequently data integrity if maintained of well as any security related positioning is also maintained.

Advantage:-

i) Improve scalability

ii) Provide extra resilience

iii) Maximum Capacity system available.

iv) Greater fiber capacity

v) Easier network expansion

vi) Can conserve switched bandwidth

vii) DWDM System Capable of longer span length

True or False in maths

1)  If A = {1,2,3} then {2,3} is proper subset of A.

True

False

Ans:- True

2) If A = {1, 2}, B = { 2, 3, 5 } and C = { 1, 2, 5 } then find A intersection B intersection C.

{2}

{1}

{3}

Ans:- {2}

What is the difference between potentiometer as an error detector and synchro as an error detector

 1) Potentiometer →  Two pots connected in uniform.

2) Synchro → Interconnection of a synchro transmitter and synchro control transformer.

3) Potentiometer → Potentiometer as an error detector associated with angular as well as linear position control system.

4) Synchro → Synchro as an error detector associated with only angular position control.

Enlist the effect of adding a zero and a pole in transfer function of system

 When a zero is added in the transfer function

1) Bandwidth increases, hence rise time decreases

2) Setting time increases

3) System more stable

When a pole is added in the transfer function

1) Bandwidth decreases hence rise time increases

2) Resonance peaks (Mr) increase

3) System become less stable