What is the work done by friction?

AI Thread Summary
The discussion focuses on calculating the work done by a flight attendant pulling a flight bag and the work done by friction. The work done by the attendant is calculated using the formula W = fdCos(θ), resulting in 5299 J. To find the work done by friction, it's important to recognize that since the bag moves at a constant speed, the work done by friction equals the negative of the work done by the attendant. The coefficient of kinetic friction can be determined using the relationship between the frictional force and the normal force, which requires further calculations. Understanding these principles and applying the correct formulas is essential for solving parts (b) and (c).
snash1057
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A flight attendant pulls her 70.0 N flight bag a distance of 269 m along a level airport floor at a constant speed. The force she exerts is 32.0 N at an angle of 52.0° above the horizontal.


(a) Find the work she does on the flight bag.


_5299_J
(b) Find the work done by the force of friction on the flight bag.


____J
(c) Find the coefficient of kinetic friction between the flight bag and the floor.

_____


i found (a) by using W=fdCos, 32.0 x 269 x Cos(25) = 5299 J

but for part (b) and (c) i cannot understand what formula to use or how to find an answer for that matter
 
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snash1057 said:
... at a constant speed...

Drawing a FBD and remembering the above quote will lead you to a solution.
 
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