# Another scheme to catch the roadrunner has failed

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Another scheme to catch the roadrunner has failed. A safe falls from rest from the top of a 37.6 m high cliff toward Wiley Coyote, who is standing at the base. Wiley first notices the safe after it has fallen 13.4 m.

How long does he have to get out of the way? The acceleration of gravity is 9.8 m/s2 .

First find the velocity at 13.4 m (v1):$v_1^2-0=2g(13.4)$.
Then find the time it takes the safe to reach ground from (37.6-13.4) m: $(37.6-13.4)=v_1t+\frac 12gt^2$.