april 27

last weekend at family fair, physics concepts were happening everywhere. my friends and i played about 10 minutes worth of games out of the whole 2 days and our favorite was the shoot the moving can game (i forget what it was called). anyway, you had to put a cork in the gun, and with pressure it would get shot out. the cork launched into a projectile flying towards the moving cans. the force from the shot cork would knock the can down. i think you had to hit down three to win. i hit three cans, but they didn't fall down down probably because the cork was not fired with enough pressure to create enough force to knock the can down. this is a picture of my friend ready to fire her gun. sorry it's kinda dark.

This weekend was exhausting and I drove A LOT. Saturday I drove from Kaneohe to Moanalua High School (for the ACT), then to Hawaii Kai, then to Hawaii Loa Ridge, then to Ward, then to school, and then finally back to Kaneohe. Then Sunday I drove from Kaneohe, to Hawaii Kai (for a community service project this time) to Kailua, then back to Kaneohe. Plus there was traffic. I was probably in the car for about 4 hours. So being on the road for so long I was able to witness many examples of the doppler effect with many ambulences speeding by, and fast, noisy cars and motorcycles driving past me. The Doppler Effect is a change in the frequency of a wave due to motion of the source and listener. As the vehicles approached me, the frequency of their sound waves were higher because the waves arrive closer together. However once the vehicle passed me and drove away, the frequency was lower because the sound waves weren't reaching me as fast. Although the frequency of the sound emitted by the source actually stayed constant, me (the listener) perceived the frequency to be changing due to the motion of both me and the source.

waves.

like we are learning now, i have noticed that when waves in the ocean pass by, it is not the water itself moving forward but rather the disturbance of the water that is moving forward. when you see a stick or ball floating in the water, it moves up and down when the waves pass by but it doesn't move forward with the wave. i barely ever go surfing but i've noticed that when i'm sitting on the board waiting for a good wave, the small waves pass by me while i stay in place. here's just a random picture of little waves coming to the shore.