Physics Question . . . Help

[deleted92121]

We have a physics exam next week and for some reason, I do not know where to go with the following question. Any general ideas or thoughts on how to solve this would be awesome.


A cannonball is dropped from rest atop a cliff of unknown height. It free falls to the ground where it enters a bottomless pit of mud. In the mud, it travels a vertical distance of 2.0 meters in 0.15 seconds under constant acceleration after which time it comes to rest. Find the unknown height of the cliff above the mud pit

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[cheesier]

We know how long it took the ball to come to a stop in the mudpit, so we can find its velocity as it entered the mudpit which is the same as its final velocity at the bottom of the cliff.

d= (v +0)/2 * t ===> 2=0.15t/2 ====> v =6.6

Now we know the initial velocity of the ball when it was dropped (0), the acceleration (g), and the final velocity as it entered the pit (6.6).

vf = vi + at ====> 6.6/10 = t

d = 1/2 at^2, plug in your values and there is your answer.