# physics

A ball is thrown horizontally from a cliff and hits the ground 4 seconds later 40 meters from the base of the cliff. How high was the cliff (rounded to the nearest tenth of a meter)?

1. 👍 0
2. 👎 0
3. 👁 1,016
1. height h is given by

h = h0 - 4.9t^2
so, to find h0, set h=0

0 = h0 - 4.9(16)
h0 = 78.4m

the horizontal distance is irrelevant to finding the cliff height

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2. 👎 0
2. 78.4

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2. 👎 0

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