November 17 2014: Meter stick with clay

Purpose: To find the height that a meter stick reaches released from a point and hitting a clay in the way. The meter stick is pinned in one of the ends.

This is a picture of our system, as possible to see, the meter stick is pinned by one of its ends, and there is a chunk of clay at the bottom.

Explanation: We are going to use video capture and Logger Pro to compute the information in a computer. After setting up the equipment, we are going to release the meter stick horizontally to its pin and let it hit the clay at the bottom. The idea is to see how high the meter stick will go. We are going to solve the problem by hand because we are able to do that after we measure the necessary information, and then compare to the results that the computer will give us.

 This is the graph that we got from recording the experiment. The y-axis determine the distance that the meter stick raised, but we have to subtract 20 cm from it because the mass of clay was 20 cm above the ground when we did the experiment.

This are the calculations that we made in order to find how much the meter stick would raise after hitting the mass of clay. We approached it by first doing conservation of energy, then conservation of momentum and finally conservation of energy again.

Summary: We can say that the lab was successful because we solved by hand and got 0.238 meters for the height that the meter stick would raise, and when we computed the information, the computer gave us a final height of about 0.280 meters. The error can be given to the friction in the pin and also by air resistance during the experiment. The height that we released can also be a factor that affected the results because we probably didn't release the meter bar exactly in the horizontal position.