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100-Meter Sprint/Dash — a Source for Interesting Calculations

Monday, September 10th, 2007

Asafa Powell Bonita Jamaica Fastest

Originally uploaded by Bonita Jamaica

On Sept. 9, 2007, Asafa Powell broke his own 100-meter sprint/dash world record, his new record is now 9.74 sec. This race and his record can be a source for interesting calculations:

1. how many steps it takes the runners to cover 100 m?

2. what is the average step size?

3. What is their speed in terms of mph?

4. How much time during the race they spend in the air (as oppose to touching the ground)?

This can be evaluated/estimated by viewing the video frame by frame.

I believe it is more than half the time.

Look at it another way, with respect to distance, not time:
Most of the 100-meter distance he covers while he is airborne. If so, in a sense, with respect to distance, he is flying. But this is a misrepresentation because he must touch the ground every step in order to propel his airborne self for the next segment of his “flight.”

5. Assuming that Asafa Powell’s weight is still 88 kg (per Wikipedia’s older article), then:

5.1. What is his acceleration?

5.2. How much force he spent?

5.3. How much energy?

Abbott and Costello, 13 x 7 = 28 (ver. 2, Navy Cook)

Monday, July 23rd, 2007
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Abbott and Costello, 13 x 7 = 28 (ver. 1, Paying Rent)

Monday, July 23rd, 2007
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Abbott and Costello, Two Tens for a Five

Monday, July 23rd, 2007
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Abbott & Costello The loan

Monday, July 23rd, 2007
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Abbott and Costello, Who’s on first?

Sunday, July 22nd, 2007
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The mathematical connection of this famous routine is not obvious. But some important math concepts are at the root of this funny skit.

After you stop laughing and, if you are like me, wipe the tears so you can see straight, you may take a minute to think about why this is so funny. Clearly it is the use of ordinary words as proper names. But “who” and “what” are not just ordinary words. These are pronouns.

Considering the history of human languages, nouns, proper names and pronouns predate numbers, constants and variables by thousands of years. More importantly natural languages, like English and Chinese are much older than formal languages like the semantic aspect of mathematics. This is a very important point to keep in mind. For math, as a language, abhors ambiguities. Math cannot tolerate confusing numbers and variables. In mathematical terms proper nouns are numbers or constants and pronouns are are variables and in “Who’s On First?” Abbott and Costello do just that — they confuse numbers or constants with variables.

I include “Who’s On First?” in my math-humor collection because what makes it funny is the absurd exchange. And these absurds are rooted in ambiguities that we may tolerate in most normal communications. For a few moments we are made to see, if not to understand, the mathematical viewpoint of such ambiguities. This is an excellent illustration of the connection of strict mathematical concepts to ordinary language. If we remember this fact, we can often make those formal mathematical ideas much easier to understand.