How to find he coefficient of kinetic friction?

AI Thread Summary
To find the coefficient of kinetic friction, the flight attendant's work on the bag and the work done by friction need to be calculated. The work done by the attendant is 5299 J, while the work done by friction is -5299 J, indicating that friction opposes the motion. The normal force acting on the flight bag can be determined by analyzing the forces in the vertical direction, factoring in the weight of the bag and the vertical component of the pulling force. The correct calculation for the coefficient of kinetic friction involves using the normal force and the frictional force derived from the work done. The final coefficient of kinetic friction is approximately 0.4397.
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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.
_-5299_ J
(c) Find the coefficient of kinetic friction between the flight bag and the floor.
____

i found part A, by 32.0 x 269 x cos(52.0) = 5299J

but i don't understand how to get part c

i keep doing 32Cos(52)=70-32sin(52)k and i get .1357, don't get what I am doing wrong HELP!??
 
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What is the matter with the value .1357?
 
the answer is .4397
 
What is the normal force the floor exerts on the flight bag?

Draw a Free Body Diagram.
 
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