Find the coefficient of friction and acceleration with masses given

[SSJBLOOD]

Homework Statement

We need to find the kinetic friction and acceleration of a half Atwood system. The masses given are 295 grams and the smaller one is 147.5 grams.

Relevant Equations

\frac{1}{2}mv^{2}=mgh
\frac{g\left(m_{2}+m_{1}μ_{f}\right)}{m_{1}+m_{2}}

I tried to use the energy route but the acceleration was not a plausible one. It was just way too big.

 

[haruspex]

What is the exact problem statement?
I see you are taking the distance for the friction as d=12m but the drop for the suspended mass is only 5m.
Since your KE takes the final velocity as applying to both masses, that should be when the upper mass has only moved 5m, no?

 

[SSJBLOOD]

Oh I see now thanks a lot

 

[SSJBLOOD]

I wasn't to sure on how to do it that was I just tried it

 

[SSJBLOOD]

The only thing we were allowed to use was a meter stick to find the coefficient of kinetic friction between the block and the table surface. We weren't given the acceleration

 

[haruspex]

The only thing we were allowed to use was a meter stick to find the coefficient of kinetic friction between the block and the table surface. We weren't given the acceleration

You must know something else or there is not enough info. Did you time it until the suspended mass hit the floor? Or did the top mass stop before it reached the pulley and you measured how far it travelled in total?

 

[SSJBLOOD]

Yeah we had time it was 3.23 seconds

 

[haruspex]

Yeah we had time it was 3.23 seconds

Then you can calculate the acceleration.