3-19-09

J.R. Martin 3/19/09 Today we started the class with a daily question. the question deals with which objects moving down an incline plane. The question is Which will roll down a hill faster, a can of regular fruit juice or a can of frozen fruit juice. A. regular fruit juice B. Frozen fruit juice C. Depends on the realative sizes and weights of the cans Take a guess or an educated prediction.

The answer is A, because the stuff inside the regular can just slides down the ramp. The frozen can the stuff inside has to go around with the can, causing it to rotate slower and letting the regular fruit juice roll faster and beat it down the ramp.

Another daily question deals with trucks parked on a hill.

The answer is A. A will tip over because the center of mass is not anywhere above the base of the object. The center of mass and gravity are used to prove that A will fall over.

After the daily questions we were given the choice to either work on page 16 called: Even More Centripetal Force Problems,(was given to us today) or work on our reading guide for our test tomorrow. The reading guide is long so you should do it so you will know what will be on the test if you do not know already. The test will have things on torque, center of mass ans gravity, and rotation.

Mr. Manning also gave us the oppertunity to earn some extra credit by finding the center of mass on two irregular shapes due Monday.