AC Through a Resistor

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What is the basic behavior of AC through a resistor?

The voltage and current remain in phase in a resistor when AC passes through it.

How does the power dissipated in a resistor differ in AC compared to DC?

In AC, power dissipated in a resistor is given by P = I_rms²R, where I_rms is the root mean square current.

What is the formula for calculating RMS voltage in a resistive AC circuit?

The formula is V_rms = V_peak / √2.

Why is impedance in a resistor the same as its resistance?

Because impedance encompasses both resistance and reactance, but in a resistor, reactance is zero.

How does the phase angle behave in a purely resistive AC circuit?

The phase angle is 0 degrees because voltage and current are in phase.

Which law governs the relationship between current and voltage in a resistor?

Ohm's Law, which states V = IR.

How can we express power in terms of voltage and resistance in AC circuits?

Power can be expressed as P = V_rms² / R.

What does in-phase imply when referring to voltage and current in a resistor?

In-phase means the peaks and zero-cross points of voltage and current occur simultaneously.

Why are resistors considered simpler components in AC analysis?

They exhibit no phase shift and their impedance equals their resistance.

What is the role of a resistor in an AC circuit?

A resistor limits the current flow and dissipates electrical energy as heat.

What impact does frequency have on a resistor in an AC circuit?

Frequency does not affect a resistor; its resistance remains constant regardless of frequency changes.

Can resistors create a phase shift in an AC circuit?

No, resistors do not cause phase shifts between voltage and current in an AC circuit.

What component in a resistor accounts for its AC properties?

The material's resistivity and physical dimensions define a resistor's AC characteristics.

How is total resistance in series resistors calculated in AC circuits?

Total resistance in series resistors is the sum of individual resistances.

What safety precautions should be considered when working with resistors in AC circuits?

Ensure resistor wattage rating exceeds power dissipation, preventing overheating.

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