Question

A sandbag is released from a hot air balloon that is 400 ft above the ground. Using the falling object model, h = −16t^2 + s, where h = height in feet, t = time in seconds, and s = initial height in feet, how long will it take for the sandbag to hit the ground? A. 4 seconds B. 5 seconds C. 20 seconds D. 25 seconds

Answer 1

B. 5 seconds

Explanation:

A graphing calculator shows the answer easily.

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h(t) = 0 = -16t^2 +400

t = √(400/16) = 5

It will take 5 seconds for the sandbag to hit the ground.