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Question
What is an Ohmic resistor?
Solution
Ohmic resistors: The resistors which obey Ohm's law are called ohmic resistors or linear resistances.
Eg: all metallic conductors like silver, aluminium, etc. For such resistors, a graph plotted for the potential difference V against current I is a straight line and the value of resistance R is the same irrespective of the value of V or I.
i.e. V ∝ I
V = IR at constant temperature.
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Assertion: The statement of Ohm’s law is K = IR.
Reason: V = IR is the equation which defines resistance.
