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October, 2006
A Federal and State of California Nonprofit Corporation
Cleophas "Mike" McAlpin...Executive Director/Chief Tutor
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October, 2006
Reggie Bush
says "It's time to pick up a little....Momentum! "
Mike says "We've been there
before at Lesson Review 3C
" Click and try our examination of the past.. year 2001
Valuable links go to: Internet Physics
Reggie Bush: My cousin:
My Mother and Father: Click on their photo Shalay
Profile
"Sorry Mr. Tackler, You missed me again! Just too much momentum for you! You see, I weigh more than you. I'm 90.8 Kilograms and and am 6 feet tall, while you're only 79 Kilograms and maybe 6 feet tall. I would have driven you backwards with a speed of 4.1 meters/second if you had just stood there. Boy, that would have really hurt you! Why? See my cousin, Shalay's "Lesson on Momentum"...below!"
All you people out there: Want to see my report card? I hope Reggie Bush doesn't get to see it! Click on... "Report Card" Shalay: Go to the next 10 or so pages to see my trek through high level physics at my Middle School in Rancho Palos Verdes!
The photos? That's my sister, Janiece (1year, 10 months) and I on the left. ( In the middle) My grandmother, Eddie Gayle, Janiece and I are in Burbank at P.F. Chang's Restaurant, Next on the right: That's me, Shalay, "chilling it"! Then, there's my cousin, Reggie Bush, Heisman Trophy winner, and star U.S.C. player, practicing "Impulse and Momentum" problems!
See "Big Fish, Little Fish" at www.physicsclassroom.com/mmedia/momentum/fca.html
My Lesson on Momentum: Reggie weighs 200 pounds and speeds along at around 100 meters in 13 seconds, I think, (that's 0.1kilometer in 13 seconds: why?) when he is in his grove! That's a momentum of 200 pounds times 100 meters in 13 seconds...but wait. Something is wrong. My units are all mixed up! I can't figure anything in this situation. I must convert to the English System or the Metric System to figure Reggie's momentum (mv), or his mass (m) times his velocity (v). When you think of velocity, just think of speed or miles per hour, or distance divided by time. Most of the scientist use "s" for distance in the formula....v= s÷ t. You can manipulate the formula to find out "s" when you know "v" and "t", or you can find "t" when you know "s" and "v". Now that's good news!
First, I must decide which System to use. I will use the Metric System since it makes more sense than the English System with its pounds, tons, inches, feet, yards, miles, pints, quarts, gallons, and a lot more that I hate to think about. Of course, the Metric System simply consists of the gram, meter, liter and a few others of lesser value. Click on the Valuable Links icon if you want to cheat and figure out "units conversions" in record time!
My grand dad taught me all about units conversions the other day. He told me to convert Reggie's weight into grams, or kilograms by multiplying 200 pounds by 454 grams/one pound or(200) (454/1) . That equals to 90800 grams. Notice the pounds in the denominator and numerator cancel out (1/1), and I am left with only grams in the numerator. This is what I want, and it assures me that my conversion is correct! But, the gram is very small, being 1/32 of an ounce (how do I know this?), and so I can divide by 1000 to convert grams to kilograms (90800/1000=90.8 Kilograms. Now let it us figure out Reggie's momentum in the Metric System. The velocity (100 meters/13 seconds) can be multiplied by 90.8 Kilograms for a value of 698.5 Kilogram -meter/second. Now that a lot of momentum! What if a defender weighs only 175 pounds, or 79 kilograms, and he is standing there waiting for Reggie.....Something has got to give if a collision occurs. Guess what it is? Which one goes along with Reggie? The tackler, of course. Why? Of course, just standing there, the tackler has no momentum. But as soon as Reggie plows into him, he and Reggie have a momentum that is equal to Reggie's original momentum, in the first place! It's called the Conservation of Momentum....quite neat, isn't it? Both Reggie and tackler can not possibly speed up, they have to slow down. To what speed?
To find out who moves where and with what velocity: mv (Reggie)=mv(tackler + Reggie).
(90.8) (7.69) = (79 + 90.8)(x) ...( tackler's weight + Reggie's Weight)(Velocity of both)...These two quantities must be equal to "Conserve Momentum"!
x= 4.1 meters/second (Reggie and tackler move forward with a velocity of 4.1 meter/ second. It's a good thing that the friction of the ground stops when they fall. They would continue going on like this if nothing stops them! Thank God for that ol' mu (µ), the coefficient of friction. That is Newton's Law of Inertia ( or his... which Law?) Look back to Previous Page and let me Know! Any corrections? I have an open mind! Let me know! I'm full of momentum now, but not so much that I can't go onto the Next Page for a bout with.....?