Help with question related to friction on an incline?

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The discussion revolves around calculating the force of friction required to keep a 560 kg car stationary on a 4.5-degree incline and determining the coefficient of static friction when ice is present. For part a, the calculated force of friction is 427 N, using the equation Ff = u x Fn. The user is struggling with part b, which involves finding the coefficient of static friction just before the car slips. It is noted that part b relates the friction force to the coefficient of friction. The conversation emphasizes the importance of understanding the relationship between these variables in physics.
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Homework Statement



A car with a mass of 560 kg is parked on a hill inclined at 4.5 degrees to the horizontal.

a.) What is the force of fricton necessary to hold the car on the slope?

b.) If there is ice on the hill and the car is about to slip, what is the coefficient of static friction?

Homework Equations



Ff = u x Fn = u x mg(costheta)

The Attempt at a Solution



The answer I got for part a

a =
0 = - (9.8sin4.5 + U9.8cos4.5)
u = 0.078
Ff = (0.078)(560)(9.8)(cos4.5) Ff = 427N


I'm stuck on Part B

Thanks.
 
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hi pokeefer! :smile:
pokeefer said:
a.) What is the force of fricton necessary to hold the car on the slope?

b.) If there is ice on the hill and the car is about to slip, what is the coefficient of static friction?
…
I'm stuck on Part B

it's just asking for the relation between friction force and the coefficient of friction :wink:
 

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