Arock is dropped off a cliff and falls the first half of the distance to the ground in 2.0 seconds. how long will it take to fall the second half?

The answer is 0.83 seconds.

Explanation:

The formula of free fall is following:

Where g=9.8 m/s^2 and t=2 seconds, the rock takes:

19.6 meters. This is the half distance of the cliff. The whole distance is 39.2 meters. So it takes:

2.83 second to fall down completely. The rock takes the second half of the cliff in 0.83 seconds

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