# I How many watts are in a gram?

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1. Apr 15, 2017

### Dembara

I am just curious on this one, if you could efficiently turn matter into energy (the whole e=mc2 thing) how much energy could you get per gram?

2. Apr 15, 2017

### jbriggs444

In a coherent system of units such as SI, you simply apply the formula. For instance, energy (in Joules) is equal to mass (in kilograms) times the square of the speed of light (in meters per second). One gram is 0.001 kg. The speed of light is 300,000,000 meters per second.

Or, you could do it the easy way. http://www.google.com "how much energy is in a gram of matter"

3. Apr 15, 2017

### phyzguy

Note that Watts is a measure of power, not energy. This is a common mistake. In SI, energy is measured in Joules, and a watt is 1 Joule/second. Thus, if the large amount of energy in 1 gram of matter is released slowly enough, the power level in Watts can be arbitrarily small.

4. Apr 15, 2017

### rootone

The only way to do that is matter/antimatter annihilation.
Best to start with Hydrogen and it's antimatter equivalent.
A gram of anti-Hydrogen is about all there is available in total, in of all the world's highest tech research places at present.