Impacts and collisions 

Some people watch hockey because they just want to see people get body checked others play hockey just to be able to deliver bone-breaking hits. So collisions are part of the game! The faster and bigger player will deliver more force than a slow and small player.

Momentum is defined as the MASS of an object times its VELOCITY, or P=mv. There is also impulse involved in hockey, it is known as simply the change of momentum, and is formally defined as the product of the force exerted to change the momentum and the time it took to do that (I=Ft). So the two formulas involved here are:

MOMENTUM

Size of a player: Homer and Apu are skating at 10m/s. Homer weighs 100Kg and Apu weighs 60Kg pounds. They collide; guess who will end up lying on the ice.

So there is a 400 Kilogram-meter per second difference between Homer and Apu. Homer has a significantly larger momentum than Apu because he is heavier. So Homer will be able to flatten Apu on the boards.

SIZE DOES MATTER!

Speed of player

Bart and Millhouse each weigh 35Kg. Bart is skating at 13m/s and Millhouse is skating at 2m/s. Millhouse is going slow because he doesn�t know how to skate. Bart skates up to him and hits him. Will Millhouse fall on the ice?

There is a 385 Kilogram-meter per second difference between Bart and Millhouse. So Millhouse will end up on lying on the ice.

IMPULSE

What happens if Homer decides to add a punch to his body check on Apu? The force of the punch is 500 Newtons and he exerts this force for 1 second.

P=400kg x m/s
PUNCH
I=Ft F=500N t=1secondI=500N x 1second
I=500Kg x m/s

So the total change in momentum on apu is 900kg x m/s. Therefore Homer just made his body check more than 2 times more powerful. To be exact Homer just increased his hit power by 55.5%. 

Example where Impulse may occur.