Question

A 52-kg snow skier is at the top of a 245-m-high hill. After she has gone down a vertical distance of 112 m, what is her total energy?
a. 125 kJ
b. 1430 kJ
Selected: c. 570 kJThis answer is incorrect.
d. 13 kJ
I need help, I am doing test corrections. How do I do this?

Answer 1

Answer:

  a. 125 kJ

Explanation:

Her total energy is the same as the potential energy she had at the top of the hill:

  PE = mgh

  = (52 kg)(9.8 m/s^2)(245 m) = 124,852 J

  ≈ 125 kJ . . . . matches choice A

_____

After skiing down 112 m, some of her initial energy is converted to kinetic energy, and some remains as potential energy. We assume the ski slope is essentially frictionless, and air resistance is negligible.