How Much Energy Is Released in Tritium Nucleus Formation?

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majormuss
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Homework Statement


A tritium nucleus is formed by combining two
neutrons and a proton. The mass of this nucleus
is 9.106 × 10–3 universal mass unit less than the
combined mass of the particles from which it is
formed. Approximately how much energy is
released when this nucleus is formed?
(1) 8.48 × 10–2 MeV (3) 8.48 MeV
(2) 2.73 MeV (4) 273 MeV


Homework Equations



E=mc^2

The Attempt at a Solution


I tried finding the energy by using what they gave me(9.106 × 10^-3) and fixing into the equation E=mc^2, but my anwser turns out 8.2 × 10^13( which obviously missing something)
 
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majormuss said:

Homework Statement


A tritium nucleus is formed by combining two
neutrons and a proton. The mass of this nucleus
is 9.106 × 10–3 universal mass unit less than the
combined mass of the particles from which it is
formed. Approximately how much energy is
released when this nucleus is formed?
(1) 8.48 × 10–2 MeV (3) 8.48 MeV
(2) 2.73 MeV (4) 273 MeV


Homework Equations



E=mc^2

The Attempt at a Solution


I tried finding the energy by using what they gave me(9.106 × 10^-3) and fixing into the equation E=mc^2, but my anwser turns out 8.2 × 10^13( which obviously missing something)

Think about what units you are using. You may need to convert units.
 


vela said:
You can't just plug the numbers you have in and get the right answer because the units don't work out.

so how do I change form Joules to Mega Electron Volts? do I multiply or divide by 1.6 *10^-19... that is where I tend to get confused.
 


Is a joule larger or smaller than a MeV?

So if I have 1 joule, should have 1*1.6*10^-13 MeV or 1/(1.6*10^-13) MeV? Which one gives a bigger answer?

Also, for mega electron volts the conversion factor is 1.6*10^-13 not -19, -19 is for electron volts.
 


majormuss said:
so how do I change form Joules to Mega Electron Volts? do I multiply or divide by 1.6 *10^-19... that is where I tend to get confused.

You also need the mass units to be right.