The question should be rephrased as: How is mass converted into energy? because, according to the reference, it's mass, not matter, that is converted into energy.
Mass is converted into energy through processes that alter the structure of atomic nuclei. It is not that matter itself is converted to energy, but rather mass can be converted into energy when the binding energy of an atomic nucleus changes.
The Conversion of Mass to Energy
This conversion is described by Einstein's famous equation, E=mc², where:
- E represents energy
- m represents mass
- c represents the speed of light in a vacuum (approximately 299,792,458 meters per second)
This equation demonstrates that mass and energy are fundamentally interchangeable, and a small amount of mass can be converted into an enormous amount of energy because the speed of light squared (c²) is such a large number.
Examples of Mass Conversion to Energy
-
Nuclear Fusion:
- Process: In nuclear fusion, light atomic nuclei, like hydrogen, combine to form a heavier nucleus, such as helium.
- Mass Defect: The mass of the resulting nucleus is slightly less than the combined mass of the original nuclei. This "missing" mass is converted into energy according to E=mc².
- Example from reference: The reference states that two protons (mass=1) should result in a helium nucleus of mass 2, but it's slightly less (mass < 2) meaning the difference in mass was converted to energy.
- Real-World Application: The Sun and other stars generate energy through nuclear fusion.
-
Nuclear Fission:
- Process: In nuclear fission, heavy atomic nuclei, like Uranium, are split into smaller nuclei.
- Mass Defect: The combined mass of the smaller nuclei is less than the original nucleus and the difference in mass has been converted into energy according to E=mc².
- Real-World Application: Nuclear power plants use nuclear fission to generate electricity.
Understanding Mass vs. Matter
It's crucial to understand that the reference clarifies that matter is not converted into energy. Instead, it is the mass that is converted into energy, through changes in the nucleus of an atom. The term “matter” refers to any substance that has mass and takes up space, whereas mass is a specific property that relates to the amount of "stuff" in an object.
| Property | Description |
|---|---|
| Matter | Any substance that has mass and takes up space. Examples include atoms, molecules, solids, liquids and gases. |
| Mass | A fundamental property of an object; a measure of its inertia and its gravitational interactions. It can be converted to energy. |
| Energy | The ability to do work. It can exist in various forms and can be converted to and from mass |
In short, processes like nuclear fusion or fission convert mass into energy by rearranging the particles inside atoms nuclei and a small amount of mass is converted to a large amount of energy.
