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How does a resistor behave in an AC circuit compared to a DC circuit?
The resistance value of the resistor in both AC and DC circuits is same irrespective of the frequency of the AC supply voltage. The change in direction of current in AC supply does not affect resistors behavior. So the current in the resistor will rise and fall according to the voltage as it rises and falls.
Why is a resistor heated by an AC current?
Exactly the same reason that heating occurs in direct current in a resistor. In both cases, heating occurs because the voltage gradient across the resistor causes each conducting electron in the resistor material to accelerate until it collides with an atom in the material.
Which resistance is more AC or DC?
As we know that frequency in DC supply is zero, so there is no skin effect (a behavior of alternating current to flow through the surface i.e. outer layer of a conductor instead of the core of the wire). in DC circuits. Due to the skin effect, AC resistance are more in AC circuits than DC supply in DC circuits.
Does a resistor in an AC circuit produce the same heat?
The average voltage is zero, but it still delivers power to the resistor and the resistor still heats up. To get the heat produced in the AC circuit to be the same as in the DC circuit, you want the rms voltage (The square root of the mean of the square of the voltage) in the AC circuit to be equal to the DC voltage in the DC circuit.
Remember that power is the rate at which energy is consumed. The energy dissipated in the resistor then is equivalent to the power it consumes multiplied by the length of time current is flowing.
What is the ratio of voltage to current in a DC resistive circuit?
In DC resistive circuits, the resistance which is the ratio of voltage to current is linear. A resistor with an AC power supply is given below In AC circuits, the voltage to current ratio is mainly dependent on supply frequency f and phase angle orphase difference φ.
How are resistors different from other passive devices?
The difference is in the use of instantaneous peak to peak value or rms value. Resistor is a passive device. It does not consume orproduce any energy. Energy here is electrical energy. But resistor dissipates electrical energy in the form of heat. In DC resistive circuits, the resistance which is the ratio of voltage to current is linear.