Light is a form of electromagnetic radiation that is visible to the human eye. It consists of photons, which are elementary particles that have both wave-like and particle-like properties. Light is characterized by its wavelength and frequency, which determine its color and energy.
The relationship between light and mass is described by Einstein's theory of relativity. According to this theory, mass and energy are interchangeable and related by the equation E=mc². This equation states that energy (E) is equal to mass (m) multiplied by the speed of light (c) squared.
The equation E=mc² does not mean that light cannot be converted into energy. In fact, light itself is a form of energy. What Einstein's equation implies is that mass can be converted into energy, and vice versa. It shows that a small amount of mass can be converted into a large amount of energy, as the speed of light squared (c²) is an extremely large value. This equation has profound implications in the field of nuclear physics, where the conversion of mass into energy occurs in processes such as nuclear reactions and nuclear fission.
So, while light is a form of energy, it can also interact with matter and be converted into other forms of energy, such as electrical energy (in solar cells) or chemical energy (in photosynthesis). The equation E=mc² provides a fundamental understanding of the relationship between mass, energy, and light.