By using the suvat equations: (a) v 2 = u 2 + 2 a s for the vertical components, so 0 2 = ( 5 s in 57 ) 2 + 2 ∗ − 9.81 ∗ s therefore s=0.896m However, since the ramp is 1.2m above the ground, the skateboarder is 0.896+1.2=2.096m above the ground.
(b) Work out the time when the skateboarder reaches the highest point v=u+at for the vertical components, so 0=5sin57-9.81 t, therefore t=0.427s Now using the horizontal components: s=ut, so s=5cos57 0.427=1.164m
The skateboarder reaches a maximum height of approximately 2.04 m above the ground and is about 1.05 m horizontally from the end of the ramp when he reaches that height.
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