- #1

ElectroMaster88

- 3

- 3

- Homework Statement
- Body A, which has a mass of 3 kg, is on a horizontal surface and is connected by a massless and frictionless string and pulley to body B, which is suspended in the air and has a mass of 2 kg. The coefficient of friction (static and kinetic) between body A and the horizontal surface is 0.2.

A horizontal force F is applied to body A to the left.

A. Calculate what the value of the force F should be in order for the frictional force between body A and the surface to be zero.

B. In what range of values should the force F be in order for the system to be in a static state? There are answers:

A. 20N

B. 14N ≤ F ≤ 26N

- Relevant Equations
- x=x0+v0t+at^2/2

v=v0+at

f=μ*N

N=mg

Newton's Second Law

I don't understand how to solve these, and I don't understand how an horizontal force can affect the friction force if it's defined by μ*N, and the additional force affect neither of those. I also don't understand how there is a range of possible forces that F can be to make the system static, if only one option can make the horizontal net force 0.

I am clearly missing something and I don't understand what.

I am clearly missing something and I don't understand what.