Pool Table Physics Lab Rap

[Verse 1]
One day when I was chillin' in the physics laboratory
The professor started tellin' a momentum story
With two balls of equal mass, prof. was telling us a fable
About how they collide on an ideal pool table
Now the energy's conserved when you add up the sum
Of kinetic and potential, so you know that ain't so dumb
Prof. said, "You take the cue ball and hit it with the cue
And smash it at the 8-ball just to see what they will do"
You don't use no English, you gotta hit it straight
And watch it do a number on that ball number eight
But how fast and which direction will the 8-ball go?
If it's hit head-on by the cue ball, do ya know?
What speed does the 8-ball have rollin' on the slate
Compared to the cue ball in its pre-collision state?

[Chorus]
In this pool game no energy is lost
The kinetic gets passed when the balls' paths cross

[Verse 2]
The principle here is that momentum stays the same
As the cue ball had when it entered the game
If the 8-ball goes right when it's hit real deft
The cue ball's gotta move off to the left
If the cue ball and the 8-ball roll at just the same speed
What's the angle between 'em? What indeed?
And after this collision where does each ball head?
(In a frictionless world, just like the prof. said)
Whatever, whichever way the billiard balls go
Momentum and energy are all ya gotta know

[Chorus]
When the ball's go bang, their momenta can change
But the total of their vectors has to stay the same

[Verse 3]
To try this out for real you gotta find a pool table
Put the 8-ball on the spot just as neatly as you're able
Now the cue ball hits the eight and gives that ball a thumper
And you mark where the two balls collide with a bumper
You take a protractor, find the angle of each path
Then you can do some real vector math
When you've marked down the vector, spot the 8-ball again
And do some more collisions until you got ten
Collect a bunch of data and draw the vectors too
On a neat sheet of paper for the prof. to review
With a list of the angles, which you can then compare
To see how off they are from being square
You write up your results based on the world that's real
And tell how close they come to Newton's ideal
With timers and cameras we could make this real cool
But to heck with that, let's just go play some pool