# Attempt to jump across a river on a motorcycle

Chan M

## Homework Statement

A physics professor did daredevil stunts in his spare time. His last stunt was an attempt to jump across a river on a motorcycle. The takeoff ramp was inclined at 53 degrees, the river was 40 m. wide and the far bank was 15 m lower than the top of the ramp. The river itself was 100 m. below the ramp. You can ignore air resistance.What should his speed have been at the top of the ramp to have just made it to the edge of the far bank? If his speed was only half the value found in (a), where did he land?

Xo = 0m
X = 40m
Ax = 0 m/s^2

Yo = 15m
Y= 0m
Ay = -9.8 m/s^2

2. Homework Equations

X = Xo + VoT + 0.5(Ax)T

Voy = Vo*sin(53)
Vox = Vo*cos(53)

X = Vox*T (since acceleration in the x-direction is zero)

3. The Attempt at a Solution

0 = 15 + VoyT - 4.9(Ay)T

0 = 15 + Vo * sin(53) * (40 / (Vo * cos(53) ) - 4.9 (40 / Vo * cos(53) )^2

My professor gave me the answer (17.8 m/s) but I still need to know how to solve the problem?

Thanks!

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