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# What is a pure resistive circuit?

## What is a pure resistive circuit?

A circuit that contains only a pure resistance (ohms) in an AC circuit is called a Purely Resistive AC Circuit. From a technical standpoint, this circuit does not contain capacitance or inductance. In these circuits, the resistors dissipate the power, while the phase of the current and voltage remain the same.

What is resistive circuit?

POWER DISSIPATION The kind of power that exists in purely resistive circuits is what is called real power. Real power is power that is dissipated in the form of heat and is measured in watts as illustrated in Figure 5.30. The power, P, is in watts, when the voltage, E, is in volts, and the current, I, is in amperes.

### What is the impedance of a purely resistive circuit?

Impedance, which is given the letter Z, in a pure ohmic resistance is a complex number consisting only of a real part being the actual AC resistance value, ( R ) and a zero imaginary part, ( j0 ). Because of this Ohm’s Law can be used in circuits containing an AC resistance to calculate these voltages and currents.

What are the power consumed in a purely resistive circuit?

In a purely resistive circuit, the current and voltage are both in-phase and all the electrical power is consumed by the resistance, usually as heat. As a result, none of the electrical power is returned back to the source supply or circuit.

#### What is the relationship of voltage and current in a pure resistive circuit?

In the purely resistive circuit, the power is dissipated by the resistors and the phase of the voltage and current remains same i.e., both the voltage and current reach their maximum value at the same time. The resistor is the passive device which neither produce nor consume electric power.

Two common examples of resistive loads are incandescent lamps and electric heaters. Resistive loads consume electrical power in such a manner that the current wave remains in phase with the voltage wave. That means, power factor for a resistive load is unity.

## How do you calculate resistive current?

Ohms Law and Power

1. To find the Voltage, ( V ) [ V = I x R ] V (volts) = I (amps) x R (Ω)
2. To find the Current, ( I ) [ I = V ÷ R ] I (amps) = V (volts) ÷ R (Ω)
3. To find the Resistance, ( R ) [ R = V ÷ I ] R (Ω) = V (volts) ÷ I (amps)
4. To find the Power (P) [ P = V x I ] P (watts) = V (volts) x I (amps)

Is impedance and resistance the same?

Resistance is a concept used for DC (direct currents) whereas impedance is the AC (alternating current) equivalent. Resistance is due to electrons in a conductor colliding with the ionic lattice of the conductor meaning that electrical energy is converted into heat.

### What is the power factor of a DC circuit?

Power factor is defined as the cosine of angle between the voltage phasor and current phasor in an AC circuit. It is denoted as pf. For an AC circuit, 0≤pf≤1 whereas for DC circuit power factor is always 1.

What is phase relation between current and voltage?

There is no phase difference between voltage and current and the current and voltage is said to be in-phase. Complete step by step answer: It is given that the circuit is pure resistive which means that there is a resistor in the circuit along with an AC source.

#### What makes a circuit a purely resistive circuit?

Purely resistance circuits consist of electrical devices, which contain no inductance or capacitance. Devices such as resistors, lamps ( incandescent ) and heating elements have negligible inductance or capacitance and for practical purposes can be considered to be purely resistive.

Do you need capacitance in a resistive circuit?

The presence of inductance and capacitance does not exist in a purely resistive circuit. The alternating current and voltage both move forward as well as backwards in both the direction of the circuit.

## Why is the power never zero in a resistive circuit?

Therefore, in a purely resistive circuit, the power is never zero. Moreover, this is due to the instantaneous values of the current and voltage being always negative or positive.

What is the PF of a pure capacitive circuit?

With pure inductive or pure capacitive circuits, the current is 90o out of phase with the circuit voltage; thus, the cos φ = 90o. Hence, the PF of these circuits is zero.