# The Naked Scientists Forum

### Author Topic: E=MC2 SI unit for E please  (Read 19323 times)

#### lucifer

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• Posts: 2
##### E=MC2 SI unit for E please
« on: 18/12/2007 19:44:23 »
E=MC2 Can someone please tell me what S.I. Unit E is in this most beautiful equation. Is it Newtons, Watts, WHAT ? Help please

#### daveshorts

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• Physics, Experiments
##### E=MC2 SI unit for E please
« Reply #1 on: 18/12/2007 19:47:59 »
In words it is
energy = mass * speed of light 2

So it has units of energy
if the mass is in kg and the speed in m/s then the unit will be kgm2s-2 or Joules

#### daveshorts

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##### E=MC2 SI unit for E please
« Reply #2 on: 20/12/2007 18:36:45 »
No the coulomb is a unit of charge not energy.

#### opus

• Sr. Member
• Posts: 326
##### E=MC2 SI unit for E please
« Reply #3 on: 20/12/2007 18:45:11 »
is charge not energy...?

#### lucifer

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##### E=MC2 SI unit for E please
« Reply #4 on: 20/12/2007 23:03:51 »
Thank you for the responses.  Can anyone give me the value of energy on Watts or the conversion formulea

#### lyner

• Guest
##### E=MC2 SI unit for E please
« Reply #5 on: 20/12/2007 23:41:47 »
To convert what to what?
One watt  (power) is one joule (energy)  per second?
And where did coulombs suddenly come from?
This is all such elementary stuff. Why not just look it all up on Wikkers? You could even buy a Keystage 4 Science book from Waterstones. It is a 'given', not a subject for discussion, any more than the score in the last FA cup final.

#### opus

• Sr. Member
• Posts: 326
##### E=MC2 SI unit for E please
« Reply #6 on: 22/12/2007 23:22:39 »
...that's us told Lucifer! Thankyou Sophiecentaur for being so magnanimous with your obviously far superior brain.

#### lyner

• Guest
##### E=MC2 SI unit for E please
« Reply #7 on: 23/12/2007 00:31:36 »
KS4 isn't superior - it's what 16 year old kids can find out from their schoolbooks.
It's not being elitist to expect people to know what, we are told, most kids who leave School already know.
All this stuff is available on Wikkers and someone else has already  gone to the trouble of writing it out in very understandable form.
en.wikipedia.org/wiki/Units_of_energy would be a start.
It involves fewer keystrokes  to get there on google  than the original question.

#### turnipsock

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##### E=MC2 SI unit for E please
« Reply #8 on: 23/12/2007 01:22:44 »
a coulomb/sec is an Amp

E= kg x (m/s)2

= Joules
« Last Edit: 23/12/2007 12:47:33 by turnipsock »

#### The Naked Scientists Forum

##### E=MC2 SI unit for E please
« Reply #8 on: 23/12/2007 01:22:44 »