Question

The same constant force is used to accelerate two carts of the same mass, initially at rest, on horizontal frictionless tracks. The force is applied to cart A for twice as long a time as it is applied to cart B. The work the force does on A is WA; that on B is WB. Which statement is correct?
a. WA = WB
b. WA = 2WB.
c. WA=4WB
d. WB= 2WA

Answer 1

Answer:

Option (c).

Explanation:

Let the mass of each cart is m and the force is F.

Time for cart A is 2t and for cart B is t.

Work done is given by the

W= force x displacement

As the distance is given by

S= u t +0.5 at^2

So, when the time is doubled the distance is four times.

So, WA = F x 4 S

WB = F x S

WA= 4 WB