Impulse Lab

Purpose:
In this lab we a cart with metal bands attached to its end, into the left end of the track. The metal bands were used to "slow down time". We pushed the red car towards the left side of the track. Because it had a metal band on the end of it, it bounced back. On the computer the graphs were able to tell us the velocity before and after the collision.


Data:
                        Impulse remains constant in a collision      

*Impulse: J=F (force) X T (time)

*Force and time are inversely proportional

*Impulse = area of force vs. times graph

Connection to the Real World:

The first connection I made to the real world would be in any play in water polo. When you are passed the ball, you need to catch the ball with a finess that essentially reduces the force of the pass hitting your hand. By doing this you enable the velocity of the ball to decrease with ease, just like the metal rings on the carts in the lab.

Collisions Lab

In class: 

This week in the collisions lab we were given two carts (one red and one blue), a computer, a track and two motion sensors that were connected to a labquest. We put the two carts on the track and sent them towards each other in two different types of collisions, one elastic and one inelastic. The sensors would send out sonar waves to the carts, and would be able to tell how far away the cart was from the senor at any given second. In the elastic collision, both of the springs on the carts were facing each other, in the inelastic collision, we have the velcro sides of the carts collide with one another.

Data:

MOMENTUM IS CONSERVED

P(total before)= P(total) after

m + v x m x v = m + v x m+ v

The two right columns on the data table explain to us what this equation above really means. As you can see, the amount of momentum decreases, meaning it is conserved.

Connection to the Real World

Any collision from the real world can be applied to this, one that comes to mind is bowling and more specifically when the bowling ball strikes the pins. The collision between the ball and the pins is inelastic. When the two hit one another, the momentum is conserved. This is exactly the same as the inelastic collision we tested during class.

Rubber Band Cart Launcher Lab

In Class:
The purpose of this lab was to calculate and find out the relationship between energy and velocity. In this lab we put a .38 kg glider on an air track, and measured its velocity when it passed through a photogate sensor we had set up about a foot down the track. We pulled the glider back, stretching a rubber band at .01 to .05 m and measured the velocity when the glider was released during each test.  After the testing was completed, we graphed the data and came up with an equation explaining the reasoning behind our graph and its slope: E=1/2mv^2. This equation tells us that the energy of the glider is equal to half of its mass multiplied by the velocity of the glider squared.

Data:

The velocity and energy have a direct relationship:

X and Y coordinates of the graph below

Graph showing the trend and relationship between Energy and the average velocity squared

Connection:
A connection that we can make to the real world is eerily similar to our previous labs connection. Last week we figured out how to store energy in a rubber band, the connection being a bow. However, this week we basically tested the other part of a bow, the arrow. When we pulled the cart backwards, stretching the rubber band back, we were loading up the rubber band with energy. The further we pulled the rubber band back, more energy was stored and the glider would move faster. This is similar to a bow and arrow because the more you pull the string back, the faster the arrow will go- just like the glider and rubber band.