Question 1127955
olve.​ (Use 4.9tsquared+v0t=​s.)
a) A bolt falls off an airplane at an altitude of 500 m. Approximately how long does it take the bolt to reach the​ ground?
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there is no upward velocity, the ground = 0, therefore
-4.9t^2 + 500 = 0
-4.9t^2 = -500
t^2 = -500/-4.9
t^2 = 102.04
t = {{{sqrt((102.04))}}}
t = 10.1 sec for the bolt to hit the ground when dropped by the plane
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​b) A ball is thrown downward at a speed of 40 ​m/sec from an altitude of 500 m. Approximately how long does it take the ball to reach the​ ground?
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thrown downward it's -40 m/sec
-4.9t^2 - 40t + 500 = 0
use the quadratic formula; a=-4.9; b=-40; c=500
the positive solution
t = 6.8 sec for the ball to reach the ground when thrown downward
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c) Approximately how far will an object fall in 6 ​sec, when thrown downward at an initial velocity of 40 ​m/sec from a​ plane?
4.9(36) + 40(6)  = 416.4 meters in  6 sec
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