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3 years ago

A rock is thrown straight down at 7.2 m/s off a bridge that is 45 m above the ground. Find the

Physics

1 answer:

iragen [17]3 years ago

5 0

The rock's height y at time t is given by

y = 45 m + (7.2 m/s) t - 1/2 g t ²

where g = 9.80 m/s² is the magnitude of the acceleration due to gravity. Set y = 0 and solve for t :

0 = 45 m + (7.2 m/s) t - 1/2 g t ² → t ≈ 3.9 s

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Whats the definition of deposition

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Deposition:

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A car traveling at 20 m/s when the driver sees a child standing in the road. He takes 0.80 s to react, then steps on the brakes

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When driver see the child standing on road his speed is 20 m/s

So here at that instant his reaction time is 0.80 s

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3 years ago

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Answer:

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b) v1 = 463.1 m/s

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Given:-

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- The time period for 1 revolution T = 24 hrs

Find:

What is the earth's angular speed?

What is the speed of a point on the equator?

What is the speed of a point on the earth's surface located at 1/5 of the length of the arc between the equator and the pole, measured from equator?

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v1 = R*w

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v1 = 463.1 m/s

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π/2 ........... s

x ............ 1/5 s

x = π/2*5 = 18°

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R' = R*cos(18)

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Answer:

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