284 reputation
18
bio website
location United States
age 48
visits member for 3 years, 7 months
seen Nov 24 '13 at 22:50

whatever.


Feb
22
accepted Dynamics of moment of inertia
Feb
22
comment Dynamics of moment of inertia
Not sure what L and V were about, but the meaning of last two equations is clear. Thanks!
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