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## Homework Statement

Cal and Henry are riding on a sled. They are trying to jump the gap between two symmetrical ramps of snow separated by a distance W . Each ramp makes an angle θ with the horizontal. They launch off the first ramp with a speed VL. Cal, Henry and the sled have a total mass m.

Find the initial launch speed VL that will result in the sled landing exactly at

the peak of the second ramp. Express your answer in terms of some (or all) of the parameters m, θ, W, and the acceleration of gravity g, Include in your answer a brief description of the strategy that you used and any diagrams or graphs that you have chosen for solving this problem. Make sure you clearly state which concepts you plan to use to calculate any relevant physical quantities.

## Homework Equations

## The Attempt at a Solution

y = y

_{o}+ v

_{y}t - .5gt

^{2}

I set y = y

_{o}because they first & second ramp are the same, so they cancel out

0 = v

_{y}t - .5gt

^{2}

v = [tex]\frac{4.9t}{sin\theta}[/tex]

the answer is this .... v = (gW / sin 2θ)1/2

I cant understand how they get that, can i get a hint