(adsbygoogle = window.adsbygoogle || []).push({}); atwood machine problem -- symbolically solving for mass?

1. The problem statement, all variables and given/known data

Symbolically solve the equation derived for the acceleration of the Atwood's machine in part 1, A-3 for the mass m in terms ofM,g, and the acceleration,a. (No numbers.)

This question is part of a lab, so of course some other information is necessary. We were finding theoretical and experimental acceleration for an Atwood's machine when the masses on both sides were the same except for a few pennies balanced on one of the masses. After finding this value, we were using it to fine the theoretical and experimental weights of the pennies.

We were distinguishing m from M: m was the much smaller mass of the pennies, and M was the mass of the weights on both sides.

2. Relevant equations

How I solved for acceleration can be found in attached image #1. The basic equation used is Newton's second law.

3. The attempt at a solution

My weak attempt at solving for mass is in the second attached image. It all seems to cancel out and I'm getting really confused. Can anyone tell me where I made a mistake, or whether I'm just using really faulty, circular logic?

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Atwood machine problem - symbolically solving for mass?

**Physics Forums | Science Articles, Homework Help, Discussion**