Calculate the power of an object which moves through a distance of 500cm in 1s on a frictionless surface by a horizontal force of 50N

Analyze the question

A horizontal force of 50 N moves an object through 500 cm in 1 s. We are asked for the power.

Concept

Work done = Force × Distance (in the direction of the force) Power = Work done ÷ Time

Always convert to SI units first: distance must be in metres, not centimetres.

Solution

1. Convert the distance: 500 cm = 500 ÷ 100 = 5 m
2. Work done = F × d = 50 N × 5 m = 250 J
3. Power = Work ÷ Time = 250 J ÷ 1 s = 250 W

The "frictionless surface" detail tells you that the 50 N force is the only horizontal force doing work, so no energy is lost to friction and you can use the formula directly.

Answer

The power is 250 W, which is option D.

Tip

Before you calculate, check the units. JAMB often gives distances in cm or masses in g to trap students who forget to convert. Remember: P = F × d ÷ t, and if the object moves at constant speed, P = F × v (here v = 5 m/s, so P = 50 × 5 = 250 W, the same result).