What are the limitations of Ohm's Law?

Ohm's law states that electric current is directly proportional to the voltage and is inversely proportional to resistance. The current-voltage relationship can be denoted as V = IR where V is voltage, I is current, and R is resistance.

Limitations of Ohm's Law

The limitations of ohm’s law are – 

  • Ohm's law doesn’t apply to unilateral electrical components like diodes as well as transistors even though they only permit current to flow just in one way.
  • The level of voltage will not be constant with respect to time for nonlinear electrical components having properties such as resistance, capacitance, etc which makes Ohm’s law difficult to apply.

For example:

  • Semiconductors such as Germanium and Silicon don’t obey Ohm’s law and are therefore called Non-Ohmic conductors.
  • A water volt-ammeter is a unilateral network, therefore Ohm’s law is not applicable to such networks.

Related Questions:

  1. What is the necessary condition for a conductor to obey Ohm's Law?
  2. Why is the curve representing Ohm's law linear?
  3. How do you find the resistance to Ohm's law?
  4. What are the 3 forms of Ohm's law
  5. Is resistance constant in Ohm's law?

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CBSE CLASS XII Related Questions

  • 1.
    If both the number of protons and the neutrons are conserved in each nuclear reaction, in what way is mass converted into energy (or vice versa) in a nuclear reaction? Explain.


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                    • 6.
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                      CBSE CLASS XII Previous Year Papers

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