How do they know energy is not destroyed? How did they calculate it?

Answer 1

Energy can be measured. When a reaction occurs, whether it be a collision of electrons or a bowling ball bouncing on one's head, the energy expended can be measured. All measurements so far show all of the energy still there in one form or another. I'm not saying that they've measured every reaction in the universe, just that the hypothesis was tested by scientific means and found to be more feasible than not, so it's now a theory. Theory by the way is a set of statements or principles devised to explain a group of facts or phenomena, that has been repeatedly tested and can be used to make predictions about natural phenomena.
When you talk about a theory being unproven, your teminology is wrong, you're talking about hypothesis.

Good Luck

Answer 2

Energy cannot be created or destroyed, but only changed from one form into another.

Most of what goes on in the universe—from exploding stars and biological growth to the operation of machines and the motion of people—involves some form of energy being transformed into another. Energy in the form of heat is almost always one of the products of an energy transformation.

Heat can be transferred through materials by the collisions of atoms or across space by radiation. If the material is fluid, currents will be set up in it that aid the transfer of heat.

Energy appears in different forms. Heat energy is in the disorderly motion of molecules; chemical energy is in the arrangement of atoms; mechanical energy is in moving bodies or in elastically distorted shapes; gravitational energy is in the separation of mutually attracting masses.

Answer 3

This is a Law, meaning it has never been disproved so we accept it as fact for now at least. This law is a very profound statement. It can even be religious for me. Imagine the universe as a fishbowl where the boundaries of the container walls are of infinite distance. All the energy and matter that is to be swirl around in this fishbowl. The swirl is time. The particular arraingement of the matter and energy at any given moment is called a frame. Our existence is a series of frames. Our frames of our bodies are extremely localized in relation to the size of the universe. So imagine if out of all that matter and energy out there, an exact copy of a paricular frame or even a partial set of your series of frames from your lifetime form if only for an instant out there somewhere. Could you call that deja vu?

Answer 4

Its not destroyed where? If energy could just be destroyed, what would it turn into?

Answer 5

You are talking about "conservation of energy". See this source, it would take way too many words for me to post here. You can gloss over the mathematical parts if you like.

Answer 6

energy isnt destroyed its just transferred its a theory because its hard to prove but it makes sense to me

Answer 7

They probably did it theoretically, because if energy were able to be distroyed our world would be very very different. I don't know really, it's good question.

Answer 8

Who is "they"?

Answer 9

idk.. bcuz i dun do it