View previous topic | View next topic

Television Sets Weighing More

Page 2 of 2
Goto page Previous  1, 2

Efros
726687.  Fri Jul 09, 2010 6:27 am Reply with quote

Go ask Einstein, he specifically included terms that enabled the application of Newtonian mechanics to non relativistic speeds, and non-Newtonian mechanics when those speeds approached that of light.

 
dr.bob
726753.  Fri Jul 09, 2010 10:20 am Reply with quote

There's no such thing as a "non-relativistic" speed. Relativity applies to any speed. Einstein gave the equation of the relativistic mass of a body as:



Where v is the velocity, and m_o is the rest mass of the body.

Note the v^2/c^2 factor in there. That produces a non-zero result for any non-zero value of v. So even if an electron is moving at 0.0000001 m/s, it's still got a (albeit vanishingly small) relativistic mass and so is still heavier than if it's completely stationary.

 
Efros
726773.  Fri Jul 09, 2010 11:04 am Reply with quote

"non-relativistic speed"

 
Posital
726802.  Fri Jul 09, 2010 2:12 pm Reply with quote

Eh? - the concept of non-relativistic speed is simply something for lazy mathematicians/modellers...

(I like the idea of simply using a google-search as a reliable source. Great improvement over "a friend told me".)

 
dr.bob
727291.  Mon Jul 12, 2010 5:11 am Reply with quote

Quite so, Posital. The phrase "non-relativistic speed" simply means "speeds at which relativistic effects are so small, classical mechanics will give you a result that's close enough to reality for most calculations." It most certainly does not mean "speeds at which relativistic effects do not apply in any way, shape, or form" since the only speed for which that is true is zero.

 

Page 2 of 2
Goto page Previous  1, 2

All times are GMT - 5 Hours


Display posts from previous:   

Search Search Forums

Powered by phpBB © 2001, 2002 phpBB Group