This picture was taken while I was in New York City for the the Economics Challenge last May. It was taken in a pub-type restaurant in Greenwich Village. It features a game of darts between Braxton Sato and myself. The dart in the outer ring of the bullseye was mine; the dart on the fringe of the board was Braxton's. Unfortunately, we were unable to continue our game. Darts is a game contingent on the laws of physics. When a dart hits the board and pierces it without falling off, the laws of momentum are at work. When the dart strikes the board, it has a momentum equal to its mass multiplied by its velocity. However, when the dart strikes board, the board exerts force on the dart over a period of time. The time multiplied by the average force is called an impulse. The impulse is also the change in momentum. The board exerts a force on the dart, continuously decreasing its momentum, and consequentially, its velocity. This continues until the velocity of the dart is 0. The dart does not bounce off of the board because by the time its forward momentum finally equals 0, it is so far submerged in the board that it is does not bounce off.

Friction: Trick or Treat?

Last Friday, in addition to being homecoming was Halloween. After the game, eating, Ho'olauleia (sp?), and the Burning of the I, my friends and I went trick or treating in Kahala. Outside of the mall, we there was a Longs shopping cart stuck in the mud. Robert climbed into the cart and I tried to pull him out of the grass. We truly are geniuses. However, when I tried pulling the cart wouldn't slide and Robert almost fell out. I was confused. I thought that when I pull an object, the object should move. However, I then remembered friction. Friction occurs when there is a force between two objects preventing them from being slid against one another. The rubber wheels and the dried mud clung together, thus making pulling the cart very difficult. When Robert went in the cart, friction increased. Friction is equal to normal force times the coefficient of friction. Since the coefficient of friction is constant, Robert's 140 pounds increased normal force by approximately 450 Newtons. Thus, our antics were impeded by the phun of friction.