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DeSean throws a ball up with an initial vertical velocity of 30 ft/s from a platform that is at ground level. How long will the ball be in the air?

1 Answer

3 votes

Answer:

Time, t = 1.875 seconds

Explanation:

It is given that,

Initial velocity of the ball, u = 30 ft/s

DeSean throws a ball from a platform that is at ground level. The equation of motion when an object is thrown vertically upward is given by the following equation as :


h(t)=-16t^2+vt+h

Here, h = 0 since, the ball is thrown up at the ground level. We have to determine the time when the ball be in air. The quadratic equation becomes :


-16t^2+30t+0=0

t = 1.875 seconds

So, the ball be in air for 1.875 seconds. Hence, this is the required solution.

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