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State Ohm'S Law. What Are Its Limitations?

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Question

State Ohm's law. What are its limitations?
Answer in Brief
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Solution

According to Ohm's law, the current flowing in a conductor is directly proportional to the potential difference across its ends provided the physical conditions and temperature of conductor remains constant.
Limitations of Ohm's law:
1. Ohm's law does not apply to conductors such as diode, radio valves, metal rectifiers, where electricity passes through gases.
2. Ohm's law is applicable only when the physical conditions remain constant.
3. Ohm's law is applicable only when the temperature of the conductor is constant.

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Chapter 4: Current Electricity - Exercise 1 [Page 209]

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Frank Physics - Part 2 [English] Class 10 ICSE
Chapter 4 Current Electricity
Exercise 1 | Q 3 | Page 209

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