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The height in meters of a projectile can be modeled by h=-4.91² + vt+s where is the time (in seconds) the

object has been in the air, v is the initial velocity (in meters per seconds) and s is the initial height (in meters). A
soccer ball is kicked upward from the ground and flies through the air with an initial vertical velocity of 4.9
meters per second. Approximately, after how many seconds does it land?

User Huxi
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1 Answer

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We can use the given equation to solve for the time at which the soccer ball lands. When the soccer ball lands, its height will be zero, so we can set h=0 and solve for t.

h = -4.9t^2 + vt + s

0 = -4.9t^2 + 4.9t + 0 (since the initial height, s, is 0)

0 = t(4.9t - 4.9)

t = 0 or t = 1

We can discard the solution t = 0, since this corresponds to the initial time when the ball is kicked. Therefore, the soccer ball will land after approximately 1 second.

User Georgia Kalyva
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