The relationship between current and voltage and resistance is described by ohlm's law. This equation i=v/r tells that the current i flowing through a circuit is directly proportional to the voltage v, and inversely proportional to resistance r. This desceibes the relationship of voltage, current and resistance.
Light is a form of electromagnetic radiation with a wavelength which can be detected by the human eye. It is a small part of the electromagnetic spectrum and radiation given off by stars like the sun. Animals can also see light. The study of light, known as optics, is an important research area in modern physics.