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State Ohm’s law. Is it always true? - Physics

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Question

State Ohm’s law. Is it always true?
Law
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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 the conductor remain constant.
No, it is not always true. E.g., Diode valve, junction diode, etc., do not obey Ohm’s law.

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Chapter 4: Current Electricity - Exercise 4.1 i [Page 173]

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Frank Physics - Part 2 [English] Class 10 ICSE
Chapter 4 Current Electricity
Exercise 4.1 i | Q 7 | Page 173

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