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- Newsgroups: sci.physics
- Path: sparky!uunet!wupost!spool.mu.edu!yale.edu!jvnc.net!newsserver.technet.sg!nuscc!matmcinn
- From: matmcinn@nuscc.nus.sg (Brett McInnes)
- Subject: Re: Question 6
- Message-ID: <1993Jan4.011207.23844@nuscc.nus.sg>
- Organization: National University of Singapore
- X-Newsreader: Tin 1.1 PL4
- References: <4fFkMz_00YUoI23Wo=@andrew.cmu.edu>
- Date: Mon, 4 Jan 1993 01:12:07 GMT
- Lines: 16
-
- st0o+@andrew.cmu.edu (Steven Timm) writes:
- : The misunderstanding of E=mc^2 is one of the most common errors made
- : on sci.physics. Since energy by itself is not Lorentz-invariant,
- : E=mc^2 is only true in the rest frame of the particle. In the rest frame
- : of the particle it has by definition no kinetic energy, just rest-mass energy.
- :
- : The mass of a particle is lorentz-invariant, and is the same no matter how
- : it is measured. You don't increase the mass of the iceberg by melting it.
- : Plus, whatever energy you add to the iceberg will be subtracted from the
- : fuel supply of your bunsen burner.
- :
- : In the case of electron and positron annihilating to form two photons,
- : here we have the case that mass is not conserved, but total energy is.
- : ^^^^^^^^^^^^^^^^^^^^^
- : Steve Timm
- Ow! Ow! Ow!
-