Coefficient of friction homework problem

AI Thread Summary
A 10kg mass slides down a 37-degree incline with a coefficient of friction of 0.4. The normal force is calculated as 78.35 N, leading to a frictional force of 30 N opposing the motion. To find the acceleration, the net force must be determined by subtracting the frictional force from the gravitational force acting down the slope. The equation F=ma can then be used to calculate the acceleration. The discussion emphasizes the importance of correctly identifying forces and applying Newton's second law.
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Homework Statement


A 10kg mass is released from rest and slides down an incline that makes an angle of 37degrees with the horizontal. The coefficient of friction is 0.4 on the incline. Determine (a) the force of friction acting to oppose the motion, and (b) the acceleration

Homework Equations


Determine (a) the force of friction acting to oppose the motion, and (b) the acceleration



The Attempt at a Solution



I first drew a free body diagram...

N = (m)(g)Cos(37)
N = 75

F = (0.4)(75)
= 30

Is that correct?
 
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yes, correct so far. Find a.
 
I am getting normal force as 78.35 N

but your method is correct.

What about part b?
 
I agree with pooface. And that's the first time I have ever said that sentence! 78 N is better.
 
To be honest, I have no idea where to go from here. Any hints?
 
calculate the force acting down the slope. then you would the friction acting one way and the force the other way.

Subtract them and get the net force. Then you can use F=ma to find acceleration.
 

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