How much energy per fission is released?

We've started A2 early and this is one of the questions set for homework.

How much energy per fission is released?

Can someone help please? ^ ^

Reply 1

physicsgirlie

That is a very vague question. It depends on which nuclide is being split, what it is being split into etc. Do you have any other information?

Reply 2

Mohit_C

Well I guess you'd have to find the change in mass when an element releases something and then that change in mass you must put in the equation E=mc^2 to find the energy released.

Reply 3

teachercol

Or use the BE per nucleon curve.

Reply 4

Neo1

If it has less mass it's because the binding energy is greater for the product formed than the original mass which had more...but isnt this mass defect used for binding the nucleons in the nuclei..why is it released as energy? Im having trouble understanding that...

Thanks...

Reply 5

U-Dawg

Mohit_C

Well I guess you'd have to find the change in mass when an element releases something and then that change in mass you must put in the equation E=mc^2 to find the energy released.

Ah thank you, that answered the next question I had which was to do with calculating binding energy.

@physicsgirlie: yeh sorry, the beginning said

"if a Uranium*235 nucleus splits into Rb*94 and Cs*142, during nuclear fission, the average increase in binding energy per nucleon is 1.1 MeV (which i don't understand how that was got but...)

Estimate the energy released?"

Reply 6

teachercol

You get it from the BE curve - which you get from the mass defects.

The energy released is the total increase in Binding energy - so you multiply by the number of nucleons.

It is strange when you first meet it - but it because we define BE to be the amount of enerygy we need to put in to separate the nucleons. If you release some energy then you need to put more in - the debt is greater.