A rope attached to a 18.0kg wood sled pulls the sled up a 22.0 degree snow-covered hill. A 9.00kg wood box rides on top of the sled.
Mass of Sled: 18kg
Mass of Box: 9kg
Angle of Incline: 22 Deg
If the tension in the rope steadily increases, at what value of the tension does the box slip?
The Attempt at a Solution
So I tried getting the overall tension that keeps the sled and box in equilibrium. So the tension is equal to the weight component down the slope which would be (27)(9.8)(sin 22). That gives that the tension is ~99N. So anything over that would make it slip but nope... apparently it's wrong.