Question

No work is done by a force on an object if

a) force is always perpendicular to its velocity

b) the object is stationary but the point of application of force moves on the object

c) the object moves in such a way that the point of application Of the force also moves

d) the force is always perpendicular to its acceleration.

Answer 1

option a and b is correct.

Option a) is correct W=F.x cosΘ here Θ is 90 so wor done is zero

Option b) is correct because x is zero .