Question

The family car runs out of gas. You have to push it up the driveway into a service station. The ramp is 4 meters long and rises 0.10 meters. The car weighs 9000 N. You push with a force of 300N. How efficient is the ramp?

Answer 1

Explanation:

slope, m = 0.1m/4m = 0.025

Theoretical effort (ignoring friction) = 9000N * 0.025 = 225 N

actual effort = 300 N

efficiency

= potential energy out / actual energy in

= 225 N / 300 N = 0.75