GPGC Weekly Class Report

7-6-2001 thru 7-12-2001

Freshmen Science

The students continued doing the activities dealing with motion. Here are some more photos of them in action.

	Sir Isaac Newton first used the term gravity. One of the interesting things in science is how to take away the effects of gravity. In this photo Jami and Kristen have filled a cup with water. The cup has a hole in the side of it and the water is pouring out.
	When the cup is dropped, the water stops flowing out from the hole in the side of the glass. The effect is neutralizing gravity.
	In this demonstration, Christine, Lauren, and Ajantha hold a catapult that has 2 pennies resting on a small piece of wood that has been glued to the bottom of a larger piece of wood. One penny is in the front of the larger wood and the other penny is resting just behind the larger wood. When the larger wood is bent and then released, the penny in the front flies forward while the penny in the rear falls straight down. Both pennies hit the ground at exactly the same time again proving one of Newton’s Laws of Motion.
	Here Lauren demonstrates centripetal and centrifugal forces. She has attached a cardboard replica of the Space Shuttle to a string. She has ran the string through a straw and attached heavy weights to the opposite end of the string. She holds the straw only and spins the Space Shuttle around rapidly. There is an outward push of power(centrifugal force). She all of a sudden stops the rotation. The space shuttle speeds up as it tries to fight the inward pull(centripetal force). This is what happens to all orbiting bodies that loses its orbit(decay). They are pulled back to the earth.

INVASION FROM OUTER SPACE(?)

	The students wore diffraction grating glasses to see the spectrum of several elements. After drawing the spectrum of six different elements, they had to use this knowledge to figure out what the mystery gas was. The answer was water vapor. Let’s see what one of those spectra looked like.-------------------------------Ü
	The students also saw the effect of different colored lights on objects. What if our sun was red or blue instead of yellow. The students also discovered the color of stars and its relationship with temperature.