I thought matter to energy conversion are only possible in nuclear reactors. Also if you’re fat and exercise to lose weight does this mean you have converted your matter into energy?
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Not a professional but the energy we make from food is not actual pure energy. Carbs are converted to energy (glucose etc (matter))
No, you don’t convert all the food into energy, but the chemical bonds between the atoms in the food. The same thing happens when you burn something – you break the chemical bonds between its atoms and combine them with oxygen, releasing energy in the process.
>if we get energy from the food we eat does this mean the food (matter) is converted into energy ?
No, it means the matter in the food is rearranged into a different chemical configuration that contains less stored energy.
> I thought matter to energy conversion are only possible in nuclear reactors.
If you want to get technical about it, the mass-to-energy conversion happens with all forms of stored energy, not just nuclear. However, in the case of food, the mass difference before-and-after is so incredibly tiny you’d never be able to measure it. Per E=mc^(2), 2000 dietary calories works out to only 93 nanograms of mass difference.
> Also if you’re fat and exercise to lose weight does this mean you have converted your matter into energy?
No, it means your body rearranged the hydrocarbons in fat into water and CO2, which you sweated/urinated/exhaled. Practically speaking, all the matter still exists, just not inside your body anymore.
The energy is contained within chemical bonds, which get broken apart by combining with inhaled oxygen. Those bonds do in theory have a mass, but the number so tiny that it can’t be measured. All the matter of food is excreted as smaller more stable molecules of water, carbon dioxide and urea.
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Energy can be stored in different forms.
Just like burning wood gives off heat energy but the wood is converted to carbon dioxide, water and ashes. The energy is released from chemical bonds – the matter is still there but in different forms.
Same thing happens with food we eat. It is basically (simplifying all the complicated processes) a slow burning process. The food is converted to sugars which react with the oxygen (why we need to breathe) and release energy. It isn’t literally burning but the chemical reaction is similar.
Nuclear energy converts very little matter to energy. It is mostly one kind of element transforming into another element and releasing energy. A little bit of mass is converted to energy but the bulk of the matter remains. Only something like anti-matter and matter reactions can convert nearly all matter to energy – but that really happens only in research labs and in very very very small quantities.
Using the example of our sun (a typical star). By the end of its life, it is estimated that it will convert way less than 1% of its mass to energy. The bulk of the matter will remain as different elements.
Your body gets energy from food in the same way we get energy from gasoline to power engines.
Gasoline is something called a “hydrocarbon” which can be reacted with oxygen in a “combustion reaction”. When that reaction happens, the chemical bonds in the hydrocarbon break and the potential energy in those bonds is “released” and we can use it to do work (in a gasoline engine, we use it to movie pistons).
Food also has hydrocarbons in it, (someone correct me if I’m wrong) which I beleive is what carbs are. Our body combusts/burns those carbs to get energy
Furthur, when you combust a hydrocarbon with oxygen it turns into other stuff, mainly CO2 and Water vapor. You (mostly) breath those out, which is how you loose weight
But nowhere along the way are you actually converting mass straight to energy. Again, all the energy we get from food (or any other fuel that we burn) only comes from the energy in the chemical Bonds, and all the matter just changes arrangements
Every chemical process is converting mass into energy… The question is just efficiently…
For example burning converts 0.00001% of mass to energy… So if you counted weight of everything going in and compare it with everything going out, it would be tiny bit off
Nuclear fission has just better efficiency… Nuclear fusion even better
Cool video about it: https://youtu.be/t-O-Qdh7VvQ
>I thought matter to energy conversion are only possible in nuclear reactors.
Have you never seen fire before?
>Also if you’re fat and exercise to lose weight does this mean you have converted your matter into energy?
Exactly so, this is literally the point of fat.
In food, the energy stored in one form of molecules got released by converting the molecules by breaking it down into other molecules. That is, the energy released is stored in the bonds of atoms.
In Nuclear reaction, the energy released is stored in the binding energy that hold the nucleus(proton+neutron core). Thus the name nuclear, from nucleus. Not exactly correct, but an easy way to visualize where the energy is. Food from bond between atom, nuclear from the core of an atom.
Edit: and yeah all these energy is stored/detected as mass.
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