A motor pulls an 800 kg roller coaster train to the top of a 70 m hill. What is the change in the potential energy of the cars?

548800J

Explanation:

Given parameters:

Mass of roller coaster  = 800kg

Height of hill  = 70m

Unknown:

Change in potential energy  = ?

Solution:

The change in potential energy is the difference between the potential energy at the bottom and at the top.

Potential energy at the bottom is 0J

  So;

      Change in potential energy  = mgh - 0

m is the mass, g is the acceleration, h is the height

  Change in potential energy  = 800 x 9.8 x 70  = 548800J