1 dimentional kinematics problem. due in 5 hours

AI Thread Summary
A bolt falls from an elevator moving upward at 7.1 m/s and reaches the bottom of the shaft in 3.6 seconds. To determine the height from which the bolt fell, the equation v = x/t can be used, where x is the height and v is the constant velocity of the elevator. The speed of the bolt upon impact can be calculated using the acceleration due to gravity, which is 9.8 m/s². The discussion emphasizes that the elevator's acceleration is zero since it moves at a constant velocity. Understanding these principles simplifies the problem-solving process for both parts of the question.
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Homework Statement


A bolt comes loose from underneath an elevator that is moving upward at a speed of 7.1 m/s. The bolt reaches the bottom of the elevator shaft in 3.6 s.
(a) How high up was the elevator when the bolt came loose?


(b) What is the speed of the bolt when it hits the bottom of the shaft?


Homework Equations


v=v0+ at
(x-x0)=vot+.5at^2
V^2=V0^2 -2a(x-x0)


The Attempt at a Solution



Im confused as if the acceleration of the elevator is constant or not, i can't seem to find it
 
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The elevator is not accelerating, it only has a velocity.
You can find the height of the elevator using the equation for velocity: v=x/t.
You are trying to find x; you have t and v.
What do you have to do to find x?

To find the speed of the bolt when it hits the ground, remember that a=v/t. You are trying to find v (the speed), and you have t. You also have a, which is the acceleration due to gravity, 9.8 m/s2. You just need to do simple algebra for both of these problems.

Oh, by the way, remember that if something just has a velocity, its acceleration is zero. The equations you have listed are more complicated than this problem requires, but when you need them later, something moving with constant velocity has zero acceleration. So you might just need the x0 + v0t parts of the equation, for example.
 
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