What does the equation E=mc^2 mean?

Answer 1

Equivalence.

Physics had long treated many things of being of entirely different natures. Matter was concrete. Absolute. It followed laws of motion and the like. Energy, on the other hand, was ethereal, zinging around and through the matter. It is not ridiculous that physicists had thought this way - this is much of our experience of the physical world.

E=mc^2, however, suggests that this is just not so.

Literally, it states that matter -IS- energy. And conversely that energy is matter. There is no 'special' status for one or the other. Baseballs have a wavelength like any chunk of energy, and energy must occur in packets like any chunk of mass. While quite simple in its statement, it is pretty staggering in its implication.

For example, it is used to explain how stars run (fusion turns minute amounts of mass into energy), explain the expansion of the universe (free energy turns into particle pairs which exert an outward pressure on space itself), and why photons which have no rest mass, can nonetheless push things around with impact (their speed and energy GIVE them mass).

If you want to use the equation itself, make sure your units match up. If you use kilograms for mass and measure the speed of light in metres per second, energy will be in joules. Hope that helps!

Answer 2

When mass m is converted to energy, the amount of energy E is equal to the product of the mass and the speed of light, squared. Thus, if the tiny amount of uranium-235 that does not wind up in fission products is converted to energy, that equation tells the energy. Likewise, if two heavy hydrogen atoms combine to form helium, the energy given off by an H-bomb is given by that equation.

Answer 3

In physics, E = mc2 is an important and well-known equation, which states an equivalence between energy (E) and mass (m), in direct proportion to the square of the speed of light in a vacuum (c2). See mass in special relativity for a discussion of the various definitions of mass which may be validly used with this equation.

The equation was first derived (in a slightly different formulation) in 1905 by Albert Einstein, in what are known as his Annus Mirabilis ("Wonderful year") Papers. In these, he showed that a unified four-dimensional model of space and time ("spacetime") could accurately describe observable phenomena in a way that was consistent with Galileo's Principle of Relativity, but also accounted for the constant speed of light. His special theory of relativity ultimately showed that the traditional (Euclidean-Galilean) assumption of absolute time and distance was incorrect, and, as a consequence, that mass and energy are different only in form.

Thus c² is the conversion factor required to sometimes convert from units of mass to units of energy, i.e. the energy per unit mass. In unit-specific terms, E (joules or kg·m²/s²) = m (kilograms) multiplied by (299,792,458 m/s)2.

Answer 4

It means that nothing that has a mass can exceed the speedd of light..

If you want o just read it.... It says energy=Mass X the speed of light squared..

If you want to understand it... It means as the speed of something goes up its mass also goes up.. As the mass reaches the spee of light its mass must go to infinite.. In order to accelerate it faster you need infinite energy.. There is no such thing as infinite energy".

Answer 5

EQUIVALENCE