Why do some physics professors use 9.8 and some use 9.81 m/s^2 for the acceleration due to gravity on Earth?
2007-10-06 19:23:19 · 5 answers · asked by Bad M 2 in Science & Mathematics ➔ Physics
These are both approximations. The value actually is an average as it differs slightly at different places around the world.
2007-10-06 19:27:12 · answer #1 · answered by Monah 3 · 2⤊ 0⤋
Maybe just because they can? I certainly wouldn't get pissy about a .1% difference in the Earths gravitational acceleration. It changes by quite a bit more than that (a bit less that 5% IIRC) depending on exactly where you are on the Planet and exactly where the Moon happens to be.
You don't suppose that some Proffs' might just -like- to be be pricks?
Doug
2007-10-07 03:04:59 · answer #2 · answered by doug_donaghue 7 · 0⤊ 0⤋
The professor using 9.8 just wants you to have to memorize less. Wikipedia says the value is approximately 9.80665 m/s². I'm sure some people use it to more decimal places than even that.
2007-10-07 02:28:49 · answer #3 · answered by Mel 4 · 0⤊ 0⤋
Lately, a lot of them are using 10 m/s^2. The figure reflects the accuracy with which we are able to measure the other parameters of a mechanics problem, like angles, distances, and times. Normally, we can't do a very good job with these in our school physics labs, so our measurements are necessarily rather crude. The rougher figures for g reflect this.
2007-10-07 02:28:24 · answer #4 · answered by 2n2222 6 · 1⤊ 1⤋
It depends how accurate the measurements are when you are doing calculations.
2007-10-07 02:43:53 · answer #5 · answered by eric l 6 · 1⤊ 0⤋