FInd the mass of a meter stick without a scale

In this lab my partner and i were trying to find out how we could find the weight of a meter stick without using a scale. We did this by performing the following experiment.



Part 1 Demo:

A. The stick was not balanced and has a torque because the lever arm and the force are to big on one side of the measuring stick.




B. The stick is now balanced, the same amount of force is being applied to both side of the meter stick, Both sides of the stick have the same length of lever arm and it is balancing on the Center of Mass.




C. When we add a weight to one end of the meter stick we have to move it so that the end with the weight has a shorter lever arm then the arm with no weight so it can be balanced.




Part 2 Planning:

These are the equations we will use for the experiment


Counterclockwise Torque= Clockwise torque

Force times Lever arm= Force times Lever arm (to find the force)
The force of gravity equals 9.8 (to find the weight)

w=mg ( to find the mass)


Part 3 the Experiment:

Counter clockwise torque = clockwise torque
Force times lever arm = Force times lever arm

.2 is the distance from fulcrum to weight.
.3 is distance from fulcrum to the center of mass.

.3 = (.98) (.2)

.3f/.3 = .196/.3

w =. 65


w=mg

.65= m (9.8)

.65 / 9.8 = m
.066 Kg


Part 4 Picture:
Follow this link and it will bring you to an example of the lab I just explained.


http://prezi.com/idgqzcbbbnd9/?utm_campaign=share&utm_medium=copy