Snowball Collision

Snowball Momentum 

For this blog I decided to record the collision of two snowball's of equal mass. Through this process, one can show conservation of momentum. The actual experiment was preformed by rolling one snowball at another with zero velocity. 

             

When the snowballs collided, the zero velocity snowball rolled the other way, while the non-zero velocity snowball moved only slightly. 

The momentum of the collision can be modeled by the following equation:

m1v1i  +  m2v2i  =  m1v1f  +  m2v2f

Where i represents the initial, and f represents the final values. The values plugged in below were found through plotting points in Logger Pro and finding velocity in the x direction. 

This graph displays the movement of the first snowball with non-zero velocity. 

This graph displays the movement of the second snowball with zero velocity, that was hit by the first. 

The following charts display data on the first and second snowball. 

   

Now to plug in the data:

(.225 kg)(3 m/s) + (.225)(0) = (.225 kg)(.52 m/s) + (.225)(.589)

.675 = .117 + .133

.675 = .25

Clearly momentum was not equal in the equation above meaning something went wrong during my process. Conservation of momentum was not proven because the values of kinetic energy differed before and after the collision. This error could have been caused by a number of mistakes. The weight of the masses could have been slightly off because they were approximated. Another possibility could be that I was slightly off plotting points in Logger pro, or my scale was off.

Since my calculations showed that energy was not conserved, I can now calculate an estimate for the amount of kinetic energy lost. I can do this by subtracting the final velocity from the initial:

1/2 (.225)(.589)^2  -  1/2 (.225)(3)^2 
=  .039  -  1.013
=  -0.9735 J

This shows that there was about -0.9735 Joules of kinetic energy lost during the collision of the two snowballs.