This is the info for the problem: A block of mass M1 = 160.0 kg sits on an inclined plane and is connected to a bucket with a massless string over a massless and frictionless pulley. The coefficient of static friction between the block and the plane is ms = 0.52, and the angle between the plane and the horizontal is q = 47°. Mass M2 can be changed by adding or taking away sand from the bucket.

It has 3 different parts. The first two I was able to solve. Part 3 asks: Suppose the coefficient of kinetic friction between the block and the inclined plane is muk = 0.36. If M2 = 217.1 kg, what is the magnitude of the acceleration of M1?

Can someone please explain how to do this?

1 answer

Write two equations, which should be the equation of motion of the two separate bodies: block and bucket. There will be an unknown string tension force T is each equation, acting in opposite directions, but the unknown acceleration "a" will be the same for both bodies. Therefore you will have two equations in two unknowns and can solve for a.