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osker246
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Homework Statement
A curve of radius 151 m is banked at an angle of 11°. An 798-kg car negotiates the curve at 94 km/h without skidding. Neglect the effects of air drag and rolling friction. Find the following.
(a) the normal force exerted by the pavement on the tires
(b) the frictional force exerted by the pavement on the tires
(c) the minimum coefficient of static friction between the pavement and the tires
Homework Equations
a=v^2/r
The Attempt at a Solution
Well for some reason which I cannot understand, I simply cannot figure out this problem. I first proceeded by making a freebody diagram, giving me...
Fnet= FN+Fg+Ff=ma
I broke up the diagram into x and y componets...
X-Component
Fnet x= FNx+Fgx+Ffx=ma
Fnet x= 0 +Fgx+Ffx=ma
Since, a=[tex]\frac{v^{2}}{r}[/tex]
-mgSin([tex]\Theta[/tex])-Ffx=[tex]\frac{mV^{2}}{r}[/tex]
Ffx= -[tex]\frac{mV^2}{r}[/tex] - mgSin([tex]\Theta[/tex])
So from here I can have the Friction force, where I can easily fund the friction coefficiant. Now I need to find normal force which I believe is...
Fn=mgcos([tex]\Theta[/tex])
Now using these equations to answer the questions above, I for some reason receive wrong answers. I can't figure out where I am going wrong either...any help is appreciated, Thanks.
The answers are
A) 8.37 kN
B)2.03 kN
C)0.244