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A punter can kick a football with an initial velocity of 48 feet per second. How many seconds will it take for the ball to first reach a height of 32 feet?

1 Answer

2 votes

Answer:

It will take the ball 1 or 2secs to reach height of 32ft

Explanation:

At maximum height, the final velocity of the object is zero. Using one of the equation of motion as shown;

S = ut + 1/2gt²

S is the height reached by the ball

U is the initial velocity

g is the acceleration due to gravity

t is the time taken by the ball to reach maximum height.

Since the object is kicked upward, g will be negative.

Given the following details

S = 32feet, U = 48ft/s g = -32ft/s

32 = 48t-1/2(32)t²

32 = 48t -16t²

16t²-48t+32 = 0

t² - 3t+2 = 0

t²-t-2t+2 = 0

t(t-1)-2(t-1) = 0

(t-1)(t-2) = 0

t = 1 or 2seconds

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