What defines resistance heating in terms of electricity?

Resistance heating, also known as resistive heating, is defined by the process of generating heat when an electric current flows through a conductor. As electricity passes through the conductor, it encounters resistance, which results in the conversion of electrical energy into thermal energy due to the collisions of electrons with the atoms of the conductor. This phenomenon is commonly utilized in appliances such as electric heaters and toasters.

The nature of this heating is distinct because it specifically arises from the inherent resistance of the material to the flow of electrical current, leading to a release of heat energy. This principle is governed by Joule's law, which states that the power of heat generated is proportional to the square of the current multiplied by the resistance.

The other options describe different mechanisms of heat generation that do not involve electrical resistance. Friction generates heat through the mechanical interaction of surfaces, chemical reactions produce heat via exothermic reactions, and combustion generates heat through the reaction of fuel with oxygen. However, resistance heating specifically pertains to the conversion of electrical energy to thermal energy due to resistance in a conductor, making it the correct definition in this context.