posted by Mike .
A 1400-kg car rounds a curve of 57-m banked at an angle of 14 degrees.
If the car is traveling at 98-km/h (27-m/s), will a friction force be required? If so in what direction?
How much friction force will be required?
Let the x-axis point toward the center of curvature and the y-axis point upward. Use Newton’s second law.
ΣFy = N• cosθ − mg − f •sinθ = 0 ...(1)
ΣFx = N• sinθ + f •cosθ = m•v²/R,....(2)
Solving the 1st equation for N, we obtain
N =( f •sin θ + m•g)/cos θ,
Substitute N to the 2nd equation and obtain friction force
f =m[(v²•cosθ/R) - g•sinθ].
this sucks. no help at all