two-terminal electric circuit component that offers opposition to an electric current. Resistors are normally designed and operated so that, with varying levels of current, variations of their resistance values are negligible (see resistance). They are available in several common forms: wirewound resistors are formed from windings of fine wire; film resistors, commonly found in consumer electronic devices, use lengths of carbon or metal film deposited on a resistive base; and carbon-composition resistors use a bonded mass of carbon powder with a phenolic binder. Some resistors are made so that their values can be adjusted (see potentiometer; rheostat). Resistors absorb power from a circuit and convert it into heat; they are normally rated for the maximum amount of power that they can safely handle. Special resistors are also produced for the integrated circuit.

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