Resistance, because the material on current generation block, so that the effect of resistance material. Resistance will cause the electron flow flux, the less resistance, the electron flow flux is large, and vice versa. No resistance or resistance is very small material called electrical conductors, referred to as conductor. Cannot form the current transfer of substances known as an electrical insulator, referred to as the insulator. Digital circuit function a pull-up resistor and a pull-down resistor.
According to this definition can know, although resistance is applied to many circuits, their functions are different, but their main functions are applied to block current flow, limiting, shunt, antihypertensive, partial pressure, load and the capacitor together for filter and block matching. Resistance is an important purpose is to protect circuit.
In the series circuit resistor used for partial pressure, in a parallel circuit, on the main road of the reciprocal of the resistance equal to the resistance in each branch on the reciprocal sum of1 / R = 1/ R + 1 / R \\\'" ... Parallel circuit resistor used for shunting.
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