A motorist runs out of gas on a level road 150 m from a gas station. The driver pushes the 1,120 kg car to the gas station.

Question

f a 120 N force is required to keep the car moving, how much work (in J) does the driver do?

Answer 1

In doing work, the motorist would exert a force of 120 Newtons through a distance of 150 meters.

Then Work equals 120 Newtons times 150 meters or 18000 Joules since a unit of "Newton-dot-meter" or N•m is known as a Joule or J.

This can be abbreviated as W = 120 N × 150 m or W = 18000 N•m or 18000 J.

(It is not required for the solution of this problem, but the acceleration of the vehicle can be found by

120 N = 1120 kg • a m/s² or (120/1120) N/kg gives acceleration or a equal to 0.1071428571 m/s².)