Physics
Define work. State the conditions when the work done by a force acting on a body is zero.
Answer
The definition of work states that when force is applied on a body and the body moves then work is said to be done.
The two conditions for the work done to be zero are,
(i) When there is no displacement of the body on application of force
i.e. S = 0 and
(ii) When displacement is normal to the direction of force
i.e. θ = 90° as cos 90° = 0
Related Questions
(a) Define couple.
(b) State the SI unit of moment of couple.
(a) What is meant by an ideal machine?
(b) Write a relationship between the mechanical advantage (MA) and velocity ratio (VR) of an ideal machine.
The given figure shows a trace of a sound wave which is produced by a particular tuning fork.
(a) Draw a trace of the sound wave which has a higher pitch than that shown in figure.
(b) Draw a trace of the sound wave which is louder than that shown in figure.
Why should a fuse with defined rating not be replaced by one with a larger rating?