Question

Andrea is going 10m/s toward a hill. She coasts up the hill without pedaling. if Friction causes 10% of her energy to be connected to heat inside the gears, how high up the hill will she be able to cast?

Answer 1

E_fr=0.1E.

From the conservation of energy:

E=K=E_fr+mgh

K=0.1K+mgh

mgh=0.9 1/2 mv^2.

h=0.45 v^2/g=0.45 〖10〗^2/9.8=4.6 m.