# Physics

A body is thrown up with a velocity of 78.4m/s.find how height will with rise and how much time if it take to return its point of rejection?

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1. the free fall equation is
... h = -4.9 t^2 + 78.4 t

max t is on the axis of symmetry
... t = -78.4 / (2 * -4.9)

find max t and plug into free fall equation to find max height

time up equals time down, so the flight time is twice max t

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2. a. V^2 = Vo^2 + 2g*h.
0 = (78.4)^2 - 19.6h, h = ?.

b. V = Vo + g*Tr. Tr = Rise time.
0 = 78.4 - 9.8Tr, Tr = ?.

Tf = Tr. Tf = Fall time.

Tr + Tf = Time in flight.

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