Einsteins - reply

["LEE COLLINS" <nlco@imag.wsahs.nsw.gov.au>]

According to my book of units (Rocke FA, Handbook of Units and 
Quantities, Australian Atomic Energy Commission - now Australian 
Nuclear Science and Technology Organisation - 1985), the Einstein is 
equal to Nhv (N=Avogadro's no., h=Planck's constant, v (Greek nu)= 
frequency). Because v is variable, so is the Einstein, and thus 
cannot be a unit. This answers the question regarding photon energy.

By the way, the comment is made in the book that the Einstein is 
sometimes wrongly supposed to be equal to N.

Hope this helps.

Lee Collins

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Lee Collins MSc FACPSEM
Chairman, Division of Allied Health
Medical Physics Dept.
Westmead Hospital
Westmead   NSW  2145  Australia

Phone : +61 2 9845 6533
Fax   : +61 2 9891 5385
email : lee.collins@imag.wsahs.nsw.gov.au
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