Question

A 30 N force toward the west is applied to an object. The object moves 50 m east during the time the force is applied. What is the change in kinetic energy of the object?
a) 1.0 J
b) 750 J
c) 1.7 J
d) -1500 J

Answer 1

Answer:

D.-1500Joules

Explanation:

The change in kinetic energy of the object s equivalent to the workdone by the body in the west direction (negative x direction)

Workdone = Force * Distance

Given

Force = 30N

Distance moved by the object = 30m

Required

Kinetic energy

Kinetic energy = 30 * 50

Kinetic energy = 1500Joules

Since the body moves in the negative  direction, hence the kinetic energy will be -1500Joules