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Einstein's famous formula states that E = mc squared. Rewrite the formula with c as the subject.

Einstein's famous formula states that E = mc squared. Rewrite the formula with c as the subject.
please help and show all your working out! 
Thank you very much!! 

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This is something I always have my physics students do.
Then tell me the meanings of each equation and which one they think is the "real" equation.
E = mc2 <= the mass of the universe and speed of light determine how much energy is in the universe.
m = E/c2 <= the energy in the universe and speed of light determine how much mass there is
c = √(E/m) <= the ratio of energy to mass in the universe determines the sped of light

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2 Answers

Hello, Kath
 
If E = mc2
 
then
 
c2 - E/m
 
and
 
c = √(E/m) or (E/m)½
 
 
Hi again Kath;
According to my college physics professor, E=mcis an over-simplification of the mathematical formula.  The way E=mc2 has been taught in the grammar schools drove him crazy.
 
Unfortunately, I no longer have my college notes.  I researched this on the internet.  In its original form, the formula is ...

E2=[(m2)(c4)]+[(p2)(c2)]
 
E=energy of the particle
m=rest mass
p=momentum, also represented as mass multiplied by velocity, (mass)(velocity), p=mv.
c=speed of light, 299,792,458 meters per second.

If the mass is not moving, then p, momentum, is zero, because velocity (speed and direction of motion) is zero...
E2=[(m2)(c4)]+[(02)(c2)]
Then this is...
E2=m2c4
The square root of both sides is...
E=mc2
As William explained, this can also be represented as...
c=√(E/m) or c=(E/m)½
 
As to the original equation, I do not know of any way of isolating c as the subject.
 
I know this does not answer your question.  I just want to ask of you not to drive your college professors crazy.