Energy problem-worker on roof of a building dropped a wrench over the edge

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SUMMARY

A worker dropped a 0.125 kg wrench from the roof of a building, reaching a speed of 33.1 m/s at the 8th floor. The building's first floor is 12.0 m high, with each subsequent floor measuring 8.0 m. By applying the equations for gravitational potential energy (Eg = mgh) and kinetic energy (Ek = 1/2 mv²), the total height of the building can be calculated, as well as the speed of the wrench just before impact and its kinetic energy at that moment.

PREREQUISITES
  • Understanding of gravitational potential energy (Eg = mgh)
  • Knowledge of kinetic energy formula (Ek = 1/2 mv²)
  • Basic physics concepts of motion and energy
  • Familiarity with units of mass (kg), height (m), and velocity (m/s)
NEXT STEPS
  • Calculate the total height of the building using the speed of the wrench at the 8th floor.
  • Determine the speed of the wrench just before it hits the ground using kinematic equations.
  • Compute the kinetic energy of the wrench just before impact using the kinetic energy formula.
  • Explore the effects of air resistance on falling objects for a more comprehensive understanding.
USEFUL FOR

Students studying physics, educators teaching mechanics, and anyone interested in understanding the principles of energy and motion in real-world scenarios.

flyingbadger
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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


Eg=mgh
m-mass, g=9.8, h-height
Ek=1/2 X mv^2
Ek-kinetic energy


The Attempt at a Solution



I have no idea how to solve this. Please help! Thank you!
 
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you know the wrench starts from 0 velocity and reaches 33.1m/s when at the height of 8th floor. can you deduce the height difference between roof and 8th floor from this info?
 

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