How Is Work Done by Friction Calculated in Physics Problems?

AI Thread Summary
The discussion focuses on a physics problem involving a flight attendant pulling a bag with a force at an angle, requiring calculations for work done and the coefficient of kinetic friction. The work done by the attendant is calculated as 7135.16 J, while the work done by friction is -7135.16 J, indicating that friction opposes the motion. To find the coefficient of kinetic friction, the relationship between friction force, normal force, and the coefficient is emphasized. Participants suggest calculating the friction force and normal force to proceed with finding the coefficient. Understanding these relationships is crucial for solving the problem effectively.
kiwikahuna
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Homework Statement



A flight attendant pulls her 60.4 flight bag
a distance of 323 m along a level airport floor
at a constant velocity. The force she exerts is
46.0 N at an angle of 61.3° above the horizon-
tal.
a) Find the work she does on the flight bag.
Answer in units of J.
b) Find the work done by the force of friction
on the flight bag. Answer in units of J.
c) Find the coefficient of kinetic friction be-
tween the flight bag and the floor.


Homework Equations


force of friction = normal force X coeffiecent of kinetic friction


The Attempt at a Solution



I have found that the work she does on the flight bag is 7135.16 J and the work done by the force of friction is -7135.16 J.
I can't seem to comprehend how to solve for the coefficient. If you can lend a hand in the right direction, I would appreciate it very much!
 
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kiwikahuna said:
force of friction = normal force X coeffiecent of kinetic friction
That's what you need. Figure out the friction force (you must have figured that one out already) and the normal force.
 
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