What is Work done and it's derivative.

work done application and formula

Work done

In our daily life work is considered as doing some effort, but in Physics it has entirely different concept, Any body doing work on other body means the first body is applying some to displace other body in other words if one body changes position of other body by applying some force that means the first body is doing some work over other, it can be expressed in mathematical equation as work done is equal to the product of force and displacement(i,e W=f.d) but when we apply the force at some angle we will have to include cosine function in the equation so it will becomeW=fdcos(theta) here theta is angle at which force is being applied to the body if we further rearrange the equation we will find that work is also product of rate of chsngr of momentum and displacement (i.e)

W=f.d we know that f=ma'

so W=ma.d since a=(vf-vi)/t here vf and vi are the final and initial velocities respectivey

=> W={(mvf-mvi)/t}xd

hence this equation is showing that work can also be defined as product of rate of change of momentum and displacement.

Some important MCQ's

MCQs # 1The periodic alternations of sound between maximum and minimum loudness is called ______.

A.Pitch of sound

B.frequency of sound

C.Beats of sound

D.Quality of sound

Answer:C

Explanation: It's definition 

MCQs # 21 torr is equal to to:

A.13.3 N/m^2

B.1.33 N/m^2

C.133.3 N/m^2

D.0.133 N/m^2

Answer: C

MCQs # 3Kilo watt-hour is unit of;

A.Power

B.Work

C.Energy

D.both  B&C

Answer: D

MCQs #4What is average density of earth?

A.5000 kg/m^3

B.5500  kg/m^3

C.4000 kg/m^3

D.4500 kg/m^3

Answer:B