# Could someone PLEASE quickly check if my work is right?

## Homework Statement

Basically there's a 1.00 kg object hanging in the air attached to a string which is attached to a 0.1487 kg object that is on a table, and they're connected with a pulley.

the 1.00 kg object pulls the 0.1487 kg a distance of 0.89 m in 1.22 s and then stops when it hits the ground, i need to find the coefficient of friction

ok so..

first i found the final velocity of the object
which is 0.89 m / 1.22 s which gave me a final velocity of 0.7295 m/s

then i found the acceleration of the entire body by doing

a = (vf - vi)/t which gave me an acceleration of 0.597957 m/s^2

The Fnet of the entire body is

Fnet = [(0.100kg ) + (0.1487kg )] * (0.597957 m/s^2)
= 0.14871 N
This is the actual net force with the friction

so the acceleration of the 0.100 kg falling down without the tension should be just

mg = (0.100)(9.8)
= 0.98 N

so the friction force should be
0.98 N - 0.14871 N
= 0.83129 N

This is the friction force.

The coefficient of friction is

Ff = uFn
so 0.83129 N = u(mg)
0.83129 N = u(0.1487 kg * 9.8 m/s^2)

u = 0.5704