Elementary Physics - Energy Related Problem

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SUMMARY

The discussion centers on a physics problem involving a 0.125 kg wrench dropped from a building under construction. The wrench reaches a speed of 33.1 m/s at the 8th floor, which is 12.0 m high for the first floor and 8.00 m for each subsequent floor. By applying the equations for potential energy (PE = mgh) and kinetic energy (KE = 1/2 mv²), participants concluded that the building has 10 floors, and the wrench's speed just before hitting the ground is calculated to be 39.4 m/s with a kinetic energy of 24.6 Joules.

PREREQUISITES
  • Understanding of potential energy (PE = mgh)
  • Knowledge of kinetic energy (KE = 1/2 mv²)
  • Basic principles of motion under gravity
  • Ability to perform unit conversions and calculations
NEXT STEPS
  • Study the relationship between potential and kinetic energy in physics problems
  • Learn about free fall and acceleration due to gravity (g = 9.8 m/s²)
  • Explore the concept of energy conservation in mechanical systems
  • Practice solving similar physics problems involving energy and motion
USEFUL FOR

Students studying physics, educators teaching energy concepts, and anyone interested in solving mechanics-related problems involving energy transformations.

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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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