Atwood Machine: Is g = 9.8 m/s^2?

[curiousgeorge99]

Homework Statement

Simple question I'm sure, but I want clarification if possible. If you do an experiment with the Atwood machine and you need to calculate 'g', should it be close to 9.8 m/s^2 ?

Homework Equations

No equations necessary, theoretical question. I would think the Atwood machine is trying to demonstrate that g is actually 9.8m/s^2 ?

The Attempt at a Solution

 

[turdferguson]

In reality, the pulley and string have mass, so the experimental acceleration will be less than the theoretical acceleration of the system

 

[curiousgeorge99]

My 'g' is calculated to be about 7.1 m/s^2, so its good to know it should be less than 9.8.