Impulse Lab

~ Big Question: "What is the relationship between impulse, force, and time?"

 ~ This week we performed a lab where we attached aluminum rings to a car and the force probe. On the other end of the track was the sonar range finder to measure the velocity of the car. Then, we were set up, we pushed the red car into the force probe with the ring. When the car with the ring hit the ring,  it changed its direction to create an elastic collision.

Then we looked at the graphs on Logger Pro to find the before velocity and after velocity of the car and the integral which is the area of the parabola in the force and time graph.

Data:

Before: 0.2625

After: -0.2997

Integral: -0.2100

Next, we had to find the impulse. Impulse is the change in velocity of the car. Impulse is equal to momentum after minus momentum before.

     Impulse: -0.7425-0.65625=-0.14055

Comparing it to the area of the parabolic shape on the graph, they are approximately the same. With this information, we can assume that the area of a force and time graph is equal to the impulse.

Football: In football, many collisions occur, whether it be elastic or inelastic. These collisions cause impulses to happen.

Tom Brady Gets Crushed: Youtube Video

In this video, Tom Brady is running forward. This means that his momentum is going forward. When he gets hit, his momentum changes and his momentum is going back. This change in momentum is the impulse. Clements, the hitter is what causes Tom Brady's impulse.

Collisions Lab

 ~ Big Questions:
"What is the difference between the amount of energy lost in an Elastic Collision vs Inelastic Collision?"

"What is a better conserved quality - momentum or energy?

 ~ This week we performed a collisions lab where we had two carts, one red and one blue, on a track. At each end of the track, we placed a sonar range finder that "picks up" the motion for each cart. We used the electronic force probe and plugged into the two carts and the computer to graph the collision.

 ~ For this lab, we had two trials: elastic collision and inelastic collision.

In the elastic collision, the clear stick was sprung out to prevent the carts from sticking together. With the blue cart at rest, we pushed the red cart towards the blue cart. When the collision occurred, the blue cart went in motion towards the left side while the red cart slowed to a stop. This is the data that we found for this type of collision.

In the inelastic collision, we put away the clear sticks for the carts and left the velcro which allowed the cars to stick together. With the blue cart at rest, we pushed the red cart towards the blue cart again. When the collision occurred, the blue and the red cart stuck together and both moved towards the left. 

 ~ To answer the big questions, our data showed that the inelastic collision had much more energy lost. Also, if we were to measure collisions, it would be better to use momentum because it better conserves. Momentum does not have that much percent difference. 

Football Collisions

 ~ In football lots of collisions occur between players. In order to start the collision, a player must have some type of momentum towards the other player. His mass times his velocity determines his momentum. With a bigger momentum, the player can cause a bigger collision.