Is Ohm's Law applicable for only DC or for both?

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SUMMARY

Ohm's Law, expressed as V=IR, is applicable to both AC and DC circuits, but its specific formulation differs. For DC circuits, the relationship is straightforward with V=IR, while for AC circuits, the correct expression is V=IZ, where Z represents impedance, incorporating both resistance (R) and reactance (X). Power calculations also differ: for DC, the formulas P=VI, P=V²/R, and P=I²R are valid, whereas for AC, the formula P=VIcos(φ) is used, where φ is the phase angle.

PREREQUISITES
  • Understanding of electrical concepts such as voltage, current, and resistance.
  • Familiarity with AC and DC circuit characteristics.
  • Knowledge of impedance and reactance in AC circuits.
  • Basic grasp of power calculations in electrical engineering.
NEXT STEPS
  • Study the differences between AC and DC circuit analysis techniques.
  • Learn about impedance and how to calculate it in AC circuits.
  • Explore power factor and its significance in AC power calculations.
  • Investigate advanced applications of Ohm's Law in complex circuit scenarios.
USEFUL FOR

Electrical engineers, students studying circuit theory, and professionals working with AC and DC systems will benefit from this discussion.

Usama Khurram
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Is ohm's law (V=IR) works for both AC and DC. PLz explain in details

Also let me know which formula is right for power calculation for AC and DC circuits. (P=VI or P=VICos)
 
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ohms law is valid for both ac and dc . but the v=ir form is not actually the ohms law . this form is only valid for dc .
in AC we use the actual expression ..
J=sigma*E
J is current density
sigma is conductivity
E is electrif field

for dc p=vi=v^2/r=i^2*r can be used
the other one mentioned by you is for ac.proton007007
 
dc: V = I*R, R = resistance
ac: V = I*Z, where Z = R + jX, X = reactance, Z = impedance

Claude
 
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