# How much Energy exacltly is an MeV?

1. Sep 16, 2009

### EinsteinII

Can anybody just tell me how much energy really 1MeV will be? Curious to know because seen a lot of powerful things like cars, tools, heavy machinery, jet engines, laser cutters and i have an idea of their power in terms of respective units. Wondering how much energy will 1MeV really carry? Please make me understand in simple way!!!!

2. Sep 16, 2009

### Staff: Mentor

1 MeV = 106 eV = 1.6 x 10-13 Joules. Not so much, but then again, elementary particles are rather small. See: http://en.wikipedia.org/wiki/Electron_volt" [Broken]

For comparision: If a one pound object falls about one foot, it would gain about 1.4 Joules of energy.

Last edited by a moderator: May 4, 2017
3. Sep 16, 2009

### Bob_for_short

For electron velocity it means v ≈ 0.87*c.

4. Sep 16, 2009

### EinsteinII

Thank you very much for that explanation! I wonder how much energy is released when One MT nuclear weapon is detonated!!!!

Last edited by a moderator: Sep 16, 2009
5. Sep 16, 2009

### Norman

I believe 1 megaton is on the order of 1015 joules

6. Sep 16, 2009

### EinsteinII

7. Sep 17, 2009

### arivero

Two interesting rods here are:

- how many GeVs is one unit of atomic mass?
- how many MeVs do you get from the fusion Deuterium->Helium?

8. Sep 17, 2009

### Staff: Mentor

He means that if an electron had a total energy of 1 MeV, it would be moving at that speed. The speed is expressed as a fraction of c, the speed of light, which acts as a "speed limit" for all massive particles.

If an electron at rest (which already has some energy due to its mass) were to be given an additional 1 MeV of kinetic energy, it would end up moving at about 0.94*c.