A motorcyclist is trying to leap across a canyon by driving horizontally of the cliff that is 70.0m high at 38.0m/s. Ignoring air resistance, use energy conservation to find the speed with which the cycle strikes the ground at a height of 35.0 on the other side of the canyon. You do not to know how wide the canyon is!

2 answers

Use conservation of kinetic and potential energies:
mgh1+(1/2)m(v1)² = mgh2+(1/2)m(v2)²

where m=mass of cyclist and cycle (cancels out)
g=acceleration due to gravity (9.81 m/s^2)
h1=70m
h2=35m
v1=38 m/s
Solve for v2
42.27m/s