Kevin Tran
Lab partners: Kevin Nguyen, Jose Rodriguez
June 2, 2017

Conservation of Energy/Conservation of angular momentum

Purpose: To determine the height of the clay/meterstick when it rises experimentally and comparing it theoretically.

Introduction: We will be setting an apparatus on a table, we will attach the end of a 1 meter stick on it. Then, we will be having a small piece of clay floor. We dropped the ruler from its horizontal height and let it gain speed. It will then collide with the clay and they will stick and reach a maximum height. To do this, we attached tape to the end of the meter stick and also taped the clay, which will allow them to stick together when collided.

Below is what the setup looks like.

I would like to note that:

Meter stick: 0.088 kg

Clay: 0.03 kg

The pivot is at 0.1 meter.

Our next step was to video the before and after collision. We set up loggers pro to allow us to find the maximum horizontal and vertical distance that the clay/ meter stick travels. As a result, loggers pro gave us a height of 0.246 meters and a horizontal distance of 0.712 meters.

Below is the moment of inertia of the stick.

Below is the work of gravitational energy to angular velocity(omega). As a result, the angular velocity is 5.48 rad/s

Below is the theoretical work after the collision of the meter stick and the clay, which we solved for angular velocity(omega). As a result, we have an angular velocity of 2.626 rad/s

Below is the work to solve for our predicted height. As a result, we have a height of 0.21 meters. 

 Below is our work for uncertainty.

Conclusion: We were able to use conservation of energy and angular momentum to find our the height of the meter stick and clay when it is going up. As a result, calculated result was different to the experimental result by 0.03 meters, which gives us a 14% uncertainty.

The cases for uncertainty could be:

-Air resistance, which could cause energy lost.

-The collision of the meter stick and clay may lose energy in the experiment.