Category Archives: Math

Q: Why is the area of a circle equal to πR2?

Physicist: To demonstrate this you typically have to use either calculus or oranges.  They both use more or less the same ideas, they’re just applied in different ways. Oranges: Imagine taking an orange wedge and opening it so that the … Continue reading

Posted in -- By the Physicist, Geometry, Math | 2 Comments

0.999… revisited

The original question was: 0.999… = 1 does not make sense with respect to my conception of the number line, I do not know much about number classes but for the number line from lets say 0 to 1 there … Continue reading

Posted in -- By the Physicist, Math, Philosophical | 30 Comments

Q: How many times do you need to roll dice before you know they’re loaded?

Physicist: A nearly equivalent question might be “how can you prove freaking anything?”. In empirical science (science involving tests and whatnot) things are never “proven”.  Instead of asking “is this true?” or “can I prove this?” a scientist will often … Continue reading

Posted in -- By the Physicist, Experiments, Math, Philosophical, Skepticism | 2 Comments

Q: Since it involves limits, is calculus always an approximation?

Physicist: Nope!  Calculus is exact.  For those of you unfamiliar with calculus, what follows is day 1. In order to find the slope of a curve at a particular point requires limits, which always feel a little incomplete.  When taking … Continue reading

Posted in -- By the Physicist, Equations, Math | Leave a comment

Q: If a long hot streak is less likely than a short hot streak, then doesn’t that mean that the chance of success drops the more successes there are?

One of the original questions was:  I understand “gambler’s fallacy” where it is mistaken to assume that if something happens more frequently during a period then it will be less frequently in the future.  Example:  If I flip a coin … Continue reading

Posted in -- By the Physicist, Math, Probability | 11 Comments

Q: Where do the rules for “significant figures” come from?

Physicist: When you’re doing math with numbers that aren’t known exactly, it’s necessary to keep track of both the number itself and the amount of error that number carries.  Sometimes this is made very explicit.  You may for example see … Continue reading

Posted in -- By the Physicist, Conventions, Equations, Math | 1 Comment