# are AC and DC resistances same?

are AC and DC resistances same?

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Resistance is the ability of a circuit or element (which is called resistor) to oppose current.
Examples of Resistors with the ability of high resistance are Wood, Air, Mica, Glass, Rubber, Tungsten etc.
Unit of Resistance is “Ohm” and it is denoted by Ω and it is represented by “R”.
AC Resistance
In Simple words, Resistance in AC circuits is called Impedance. Or
The Overall resistance (Resistance, Inductive reactance and Capacitive reactance) in AC circuits is called Impedance (Z)
DC Resistance
We know that there is no concept of Inductive and Coactive reactances in DC Circuits. i.e. capacitive and inductive reactances in DC circuits zero  because there is no frequency in DC circuits, i.e. magnitude of DC current is constant. Therefore, only the original resistance of wire comes into play.
they are not the same

Capacitive reactance in DC circuit is not 0, it is actually infinite.

Xc=1/(2*pi*f*C)

## Related Questions

What is the advantage of AC over DC electrical transmission?

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Last Answer : The reason is torque. torque is inversely proportional to speed..i.e when th knowe train comes to rest position to motion.. initial speed is zero..so it requires high starting torque for ... current will flow through field and armature coils then maximum torque is available at the intial condition.

Why is AC considered more efficient than DC?
Last Answer : Ac is more efficient than dc because it is easy to maintain and change the voltage of ac for transmission and distribution purpose. Plant cost of ac transmission is much lower compared to dc transmission. When fault occurs it is easy to interrupt ac supply.

Which is more dangerous AC or DC and why ?
Last Answer : Dc is more dangerous than Ac because in Ac the voltage  will varies but in dc the constant voltage

What is the conversion between. AC to AC ? DC to DC? AC to DC? DC to AC ?
Last Answer : 1.ac to ac is regulation 2.dc to dc is chopper 3.ac to dc is rectifier 4.dc to ac is inverter

Is the power line voltage available in our homes a dc or an ac voltage?
Last Answer : The power line voltage available in our homes is AC. Mobile dwellings are the most commonly DC-supplied homes and even then they tend to include AC supply for heavier loads.

Distinguish between AC and DC.
Last Answer : Particulars Direct Current Alternating Current Definition It is the current whose magnitude and direction do not change with respect to time. It is the current whose ... system, electroplating, Battery charging, Traction. AC machines, Domestic and industrial supply.

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Compare the AC and DC Arc lamps.
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Is electricity generated in AC or DC?
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What is the difference between AC and DC drive?
Last Answer : AC means alternating current It's Frequency is 50hz Dc means direct current ItsI Frequency is 0Hz

What is the use of AC and DC drives?

Is it AC or DC electricity in the home?
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Last Answer : No, Transformer cannot convert AC to DC.

Last Answer : NO IT ONLY CONVERT FROM AC TO DC BECAUSE DIODE WHICH ARE USED IN IT, ARE UNIDIRECTIONAL.

Last Answer : IT CHANGES NEGATIVE CYCLE IN TO POSITIVE CYCLE FROM AC CURRENT.

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Series parallel resistances problem solution
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With three resistances connected in parallel, if each dissipates 20 W the total power supplied by the voltage source equals?
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Two resistances Rl and Ri are connected in series across the voltage source where Rl>Ri. The largest drop will be across?
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In a series circuit with unequal resistances?
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Last Answer : Resistances can be measured with the help of ohmmeters and resistance bridges.

Changeover from D.C to A.C
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Describe the difference between direct and alternating current.
Last Answer : Direct current is the flow of electricity or charge in one direction..  Alternative current is the flow of charge that doesn't flow in one direction.

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AC Circuits with Resistance but No Reactance
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