In Physics, What is Resistance?
In physics, resistance is defined as the ability of a substance to prevent or resist the flow of electrical current. A substance resists electrical current because of a collision between electrons and atoms, which slows the electrons down and converts some of their energy to heat energy. In some cases, the energy is also converted into light. Some substances resist electrical current more than others. For example, copper resists less than plastic, which means electricity flows more readily through copper, a good conductor, than it does through plastic. Likewise, copper resists less than glass, which is considered an insulator. German physicist Georg Ohm (1789-1854) is credited with discovering the effect of a material’s make up, length and thickness on its resistance. In fact, the standard unit of measuring resistance, the ohm, is named after him. Ohm’s law became publicly known in 1827 and states that a circuit’s resistance is one ohm if a one-volt voltage makes one amp of current. Ac
