A complex question which has mass, time and acceleration involved

AI Thread Summary
A lift accelerates upward at 1.25 m/s² while a bolt falls from its ceiling, initially 2.75 m above the floor. To determine the distance the bolt falls, one must calculate the time it takes for the bolt to fall and how far the lift moves during that time. The equations s = (a*t²)/2 and t = v/a are essential for these calculations. The total distance the bolt travels includes both the distance it falls and the distance the lift ascends during that time. Solving these simultaneous equations is necessary to find the actual distance the bolt falls.
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A lift ascends with an upward acceleration of 1.25ms-2. At the instant its upward speed is 2.5ms-1, a loose bolt falls from the ceiling of the lift, 2.75m from the floor. Calculate the actual distance the bolt falls.


(The following equations are in no particular order but may be useful)

1.)t=square root of (2Xs/a)
2.) s=aXt2/2

As i attempted the solution, my teacher told me that there were two distances involved.
 
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Draw a picture. Do you know how long the bolt will fall for? Not really because you don't really know how far up the lift will move while it's falling. Sounds like your going to have to solve some simultaneous equations.
 
First you have to calculate how far did the lift bottom go from the ground. You can use the equation s= (a*t2)/2. You can calculate the time: t=v/a.
When you calculate s (that is the height for the lift bottom), add it to the lift height and you will get traveling height of the bolt.
 
nealh149 said:
Draw a picture. Do you know how long the bolt will fall for? Not really because you don't really know how far up the lift will move while it's falling. Sounds like your going to have to solve some simultaneous equations.

Thanks for the tips. Uh Oh, I seem to have forgotten what simultaneous equations
 
method_man said:
First you have to calculate how far did the lift bottom go from the ground. You can use the equation s= (a*t2)/2. You can calculate the time: t=v/a.
When you calculate s (that is the height for the lift bottom), add it to the lift height and you will get traveling height of the bolt.

Ok Thanks I'll try that
 
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