Question

a 40 kg-skier starts at the top of a 12-metter high slope. at the bottom she is travling 10 m/s. how much energy dose she lose to friction

Answer 1

Potential energy at the top = (mass) x (gravity) x (height)

= (40 kg) x (9.8 m/s²) x (12 m)

= 4,704 Joules


Kinetic energy at the bottom = 1/2 (mass) x (speed)²

= 1/2 (40 kg) x (10 m/s)²

= 2,000 Joules .


Energy lost between the top and the bottom

(4,704 joules) - (2,000 joules)

= 2,704 Joules