$.$ In Part A$,$ how close was the experimentally determined center of gravity of the ruler to its

theoretical value. Give both values, the difference in mm$,$ and the percent error. What factors

could cause this discrepancy?

$2.$ From Part A analysis, what is the percent error between the calculated and measured values

of the moment arm? From Part B$,$ what is the percent error between the calculated and

measured mass $($recall there was some uncertainty in the washer mass$).$ From Part C$,$ what is

the percent difference between the torque values calculated on each side of the pivot? Should

they be equal? Discuss possible sources of error in the experiment.

$3.$ What are the conditions for rotational equilibrium?

$4.$ What is the difference between a positive and a negative torque?