Elementary Physics - Energy Related Problem

AI Thread Summary
A worker dropped a 0.125 kg wrench from a building under construction, and it reached a speed of 33.1 m/s on the 8th floor. The building's first floor is 12.0 m high, with each subsequent floor measuring 8.00 m. To find the total number of floors, the height difference between the roof and the 8th floor must be calculated, along with the wrench's speed just before impact and its kinetic energy at that moment. The relationship between potential energy and kinetic energy is crucial for solving the problem. Understanding these concepts simplifies the solution process.
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Homework Statement


A worker on the roof of a building that is under construction dropped a 0.125 kg wrench over the edge. another workman on the 8th floor saw the wrench go by and determined that its speed at that level was 33.1 m/s. the first floor of the building is 12.0m high and each successive floor is 8.00m high. Neglecting air friction, how many floors does the building have? How fast was the wrench falling just before it hit the ground? What was its kinetic energy just before it hit the ground?



Homework Equations


PE=mgh
m-mass, g=9.8, h-height
KE=1/2 X mv^2
Ek-kinetic energy
PE = Potential Energy
KE = Kinetic Energy

The Attempt at a Solution


I don't really have any idea on how to solve this...it was a prize question by my teacher. Thanks in advance for any help!
 
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First thing to do is to determine how much higher the top of the roof is than the 8th floor where the other workman somehow determined the speed of the wrench.

Hint: How does potential energy relate to kinetic energy in this problem?
 
Nevermind, I just thought the problem was more intimidating than it really was. Thank you for your help though! :biggrin:
 

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