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Today's fascinating physics fact...


Nuclear bombs generate their 'blast energy' according to Einstein's equation e=mc2 (energy released = mass x speed of light squared).


So a 20 kiloton bomb (the size they dropped on Nagasaki) lost about 0.8 grams of mass - about the weight of a five pound note.


So as you stroll into the pub tonight, it's worth considering that you're packing the equivalent of 5 or 6 nuclear bombs in your wallet.


Scary eh?

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Yeah. The really wierd thing is that although the bomb materials lose mass, they don't actually lose any material.


This is because the 'mass' of an object isn't just defined by the particles it's made up of, but by the energy within them.


A good example is water: water is made up of two hydrogen atoms and one oxygen atom. However, water (h2o) actually has lower mass than 2 x hydrogen and 1 x oxygen atoms, even though nothing has disappeared.


As you've probably guessed, this is because they're in a lower 'energy state' - so energy is released when hydrogen and oxygen are combined to create water.


This is how the Space Shuttle main engine works - it combines hydrogen and oxygen releasing the energy. Hence that big plume of 'smoke' out of the back isn't smoke at all - it's water.


In a nuclear bomb the by products of nuclear fission have the same 'particles' that they had before: they just have lower mass.


Freaky.

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It took me 18 clicks to get from:


Naftoruon

Naftoruon is a village in the municipality of Osak?cə in the Lankaran Rayon of Azerbaijan - this was a random article selection.


to


Property (Philosophy)In modern philosophy, mathematics, and logic, a property is an attribute of an object


It's like an intelligent variation of Six Degree of Kevin Bacon.

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I have never thought of chemical reactions such as burning hydrogen as producing changes in mass so thankyou hugs for enlightening me.

Though for the casual observer, producing water from oxygen and hydrogen is not a 'nuclear' reaction in the same vein as an atomic bomb. The changes in energy state are to do with electrons and not part of the nucleus.

Agreed?

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