Physics Photo of the Week

MARCH 9, 2012

Bumper Can Crush - Discussion by Julian Dominic
In this experiment we wanted to see what would happen when two large objects collide with each other!  Will a heavier group of men exert more force upon that of a lesser mass when going head on?  While we tried to avoid using a large vehicles in this experiment we settled with a small cart and three innocent bystanders; Julian, Calder, and Maddy.
To find out which cart (uneven mass on each) was to exude the most force upon the other we fixed on the front of both carts a set of four cans. This way, the carnage of the destroyed cans would tell us whose force (Julian and Calder’s or Maddy’s) cart exuded the most force. It was expected that Julian and Calder weighing in collectively at about 350 pounds will create more damage upon Maddy’s (weight of about 110)!

To find this out both carts were pushed towards each other by two classmates - one for Maddy and one for the 350 pounders.  What happened was astounding! And, as our good friend Sir Isaac Newton states, for every action there is an equal and opposite re-action. As for the 350 pounders, their force, although their mass was greater, was equal to the reaction force provided by the lesser mass!  As a result, the cans mad
e an astounding reaction. As you can tell in this image below, the carts were pushed slightly to one side thus only one can on each cart hadn’t collided. But, we can tell that each can was crushed to smithereens equally!

A slow motion video is included so we can see the reactions of the inhabitants of the two vehicles.  The passenger in the small vehicle suffers the most "damage", but the bumpers are crushed equally.

Julian, Maddy, and Calder are students enrolled in Earth, Light and Sky at Warren Wilson College.

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