A 40 kg skier starts at the top of a 12-meter high slope at the bottom she is traveling 10 m/s how much energy does she lose friction?

A. she doesn't lose any because mechanical energy is always conserved

B. 4,704 J

C. 2,000 J

D. 2,704 J

Potential energy at top:

PE = mgh

PE = 40 x 9.81 x 12

P. E = 4,708.8 J

Kinetic energy at bottom:

KE = 1/2 mv²

KE = 1/2 x 40 x 10²

K. E = 2,000 J

P. E = K. E + Frictional losses

Frictional losses = 4708 - 2000

Frictional losses = 2708 J

The answer is D.