Question

A 16kg sled starts up a 28 degree incline with a speed of 2.4m/s . The coefficient of kinetic friction is = 0.27.
part a)How far up the incline does the sled travel?

part b)What condition must you put on the coefficient of static friction if the sled is not to get stuck at the point determined in part (a)?

Answer 1

KE =m•v²/2,
PE =m•g•h = m•g •s•sinα,
W(fr) = F(fr) •s = k•m•g•cosα •s

KE = PE +W(fr)
v²/2 = g •s(sinα + k•cosα),
s = v²/2•s(sinα + k•cosα),

Answer 2

KE =m•v²/2,
PE =m•g•h = m•g •s•sinα,
W(fr) = F(fr) •s = k•m•g•cosα •s

KE = PE +W(fr)
v²/2 = g •s(sinα + k•cosα),
s = v²/2•g•(sinα + k•cosα),