News for hackers. Stuff that matters.

A comment on U.S. eyes building nuclear power plants on the moon, Mars. Parent comment

Re:U.S. eyes building nuclear power plants on the moon, Mars by ginko on Sunday July 26, 2020 @09:06AM (#23956784)
That's the point though. Just refer to it in joules.
[ Parent | on HN ]
Re:U.S. eyes building nuclear power plants on the moon, Mars by lukeschlather on Sunday July 26, 2020 @11:02AM (#23957539)
It's kind of like radians vs. degrees. Degrees seem ridiculous if you're doing trig, but working with irrational fractions of pi is ridiculous if you're trying to measure with a protractor. If you need to convert to radians to do some trig (and let's be honest you usually don't) you are going to end up converting something like degrees that are marked on the protractor anyway.
[ Parent | on HN ]
Re:U.S. eyes building nuclear power plants on the moon, Mars by thaumasiotes on Sunday July 26, 2020 @11:34AM (#23957802)
> Degrees seem ridiculous if you're doing trig

Degrees are ridiculous if you're doing calculus. They don't really pose any problems if you're doing trig.

> but working with irrational fractions of pi is ridiculous if you're trying to measure with a protractor.

Sure, that's true, but that's only because irrational numbers are by definition infinitely precise. It's no more difficult to use a protractor labeled in increments of 0.02 radians than one labeled in increments of one degree.

[ Parent | on HN ]
Re:U.S. eyes building nuclear power plants on the moon, Mars by rrrrrrrrrrrryan on Monday July 27, 2020 @11:02PM (#23971889)
360 is evenly divisible by 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, and 20.

0.02 radians would absolutely be a ridiculous unit of measurement if you were a carpenter or draftsman in the age before computing.

[ Parent | on HN ]
Re:U.S. eyes building nuclear power plants on the moon, Mars by thaumasiotes on Tuesday July 28, 2020 @08:45PM (#23982303)
> 360 is evenly divisible by 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, and 20.

But if you're trying to measure an angle, this is totally irrelevant. The angle is whatever it is.

[ Parent | on HN ]
Re:U.S. eyes building nuclear power plants on the moon, Mars by lukeschlather on Sunday July 26, 2020 @01:49PM (#23958761)
30/60 degrees are round numbers which are very useful for a lot of applications. Your .02 radian protractor doesn't have a mark on it for either.
[ Parent | on HN ]
Re:U.S. eyes building nuclear power plants on the moon, Mars by thaumasiotes on Sunday July 26, 2020 @02:00PM (#23958856)
Realistically, it probably would; those marks would just not fit into the progression of .02 radian marks. Ever seen a meter stick that also measured inches?

Are you trying to measure an angle, draw a particular angle, or confirm that an angle meets a particular standard?

[ Parent | on HN ]
Re:U.S. eyes building nuclear power plants on the moon, Mars by gspr on Monday July 27, 2020 @03:54AM (#23963044)
That's a general statement I'd agree with, but it's a losing battle. So many consumer products are rated by power that "I turn this 2000 W thing on for 1 hour, thus it consumes 2000 Wh of energy" is kind of convenient, if weird.

My real surprise and problem comes with Wh/x, where x is any unit of time. Why not cancel h/x for any dimensionless factor? This is what the grandparent is referring to.

[ Parent | on HN ]