Help finding coefficient of friction

AI Thread Summary
The discussion revolves around calculating the minimum coefficient of static friction required for a 1600kg car on a 16-degree ramp. The user consistently arrives at a coefficient of 0.395, while the textbook states it should be 0.365. The user provides their free body diagram and equations for forces and moments, leading to values for normal force and friction force. Despite following the equations, the user is uncertain about where their calculations diverge from the textbook answer. Clarification on the correct approach or identification of errors in the calculations is sought.
Soshamim
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Hey, I was wondering if someone could help me with this statics problem.

The question is: "The 1600kg car is just beginning to negotiate the 16* ramp. If the car has rear-wheel drive, determine the minimum coefficient fo static friction required at B.

My FBD:
attachment.php?attachmentid=8335&stc=1&d=1163575175.jpg


The answer I keep getting is 0.395, but the book says Us = 0.365.

I'm about to type up my work in a second
 

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\Sigma \vec{F}_{x} = \vec{f}_{B} - \vec{A} sin(16) = 0
\Sigma \vec{F}_{y} = \vec{B} + \vec{A} cos(16) - G = 0
\Sigma \vec{M}_{B} = -1.475*G + 2.545*\vec{A} cos(16)

...From moment equation, A = 9463N
...From Fy equation, B = 6599N
...From Fx equation, Fb = 2608N

Using Fb = u*B, I get u = 0.395, which is not the correct answer. I'm not really sure what I'm doing wrong here.
 
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