JustJeff

284 reputation

bio	website
	location	United States
	age	47
visits	member for	2 years, 5 months
	seen	Sep 6 '12 at 16:53
stats	profile views	36

whatever.

	284 reputation	bio	website		visits	member for	2 years, 5 months
17 badges		location	United States		seen	Sep 6 '12 at 16:53

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Feb 21	comment	Dynamics of moment of inertia the problem here is what happens when gamma is a function of time, or of the angular position of the system. i believe what you have is correct for constant gamma, though, as it looks exactly like the math for dealing with transformed impedances in the electrical domain.
Feb 21	accepted	what does 'same energy as a ton of TNT' mean?
Feb 21	asked	Dynamics of moment of inertia
Feb 20	asked	what does 'same energy as a ton of TNT' mean?
Feb 20	comment	Why do car keys have longer range when held next to your head? try holding it a half-wavelength from your head (reinforcing reflection) and compare that to holding it a quarter-wavelength (interfering reflection). Any difference?
Feb 16	comment	Visibility of moon-based laser from Earth @fortran - yeah, no doubt. So assume nice clear skies w/little pollution.
Feb 16	awarded	Student
Feb 16	awarded	Scholar
Feb 16	accepted	Visibility of moon-based laser from Earth
Feb 16	comment	Visibility of moon-based laser from Earth i think you've convinced me. conclusion - you'd need ridiculously stupendous amounts of power, and even then you'd just be changing the tint of one spot, which could easily be missed. so, if you wanted to undeniably prove to people 'hey, someone is mucking about on the moon', you'd probably have better luck as BarsMonster suggests, using a large Xe-flash.
Feb 16	comment	Visibility of moon-based laser from Earth yeah, it's how to think about how the laser (or Xe lamp) competes with the diffuse scattering that stumps me. fwiw, i only said laser b/c i figured the inherent directionality would deliver light on target better, but if you start from input power, you're probably right about the efficiency.
Feb 15	asked	Visibility of moon-based laser from Earth
Jan 17	comment	Reaching speed of light obviously something's going to stop you from getting to c, but what about getting to interesting fractions of c, say, just enough for relativistic effects to become noticable?
Jan 17	comment	Reaching speed of light simply as a practical matter, it's doubtful you could find a material strong enough to withstand the tension to supply the necessary centripetal force.
Jan 4	comment	Would you be weightless at the center of the Earth? @David Zaslavsky: ok, point conceded. i should have realized this would be the same thing as why there's no electric field inside a vandegraff generator, which i do recall solving the equations for (homework, back in the day) so I deleted my earlier bonehead comment.
Jan 3	awarded	Commentator
Dec 31	answered	Have the Rowan University “hydrino” findings been replicated elsewhere?
Dec 16	awarded	Critic
Dec 11	answered	Home experiments to derive the speed of light?
Dec 11	comment	Orbital mechanics of Dragon's Egg maybe whoever can answer this could also explain how six asteroids, orbiting their common center of gravity, while collectively orbiting a neutron star, could possibly be stable with the kind of tidal forces that would be present.