Assertion: the statement of Ohm's law is V=IR.
Reason: V=IR is the equation that defines resistance.
Answers
The complete question is that is the assertion and reason both are true or not.
The answer is assertion is true but the reason is false, explanation to the question is as follow :----
Ohm's law states that V is directly proportional to the current flowing through a resistance or wire.
V ∝ I
Example: If I connect a battery to the wires then the current flowing through them will increase if we increase the potential of the battery condition that resistance value does not change. Resistance values depends on dimensions of the wire and even the temperature. Accuracy in the relation can be obtained if we maintain the pressure, dimensions and temperature of the wire and we can certainly say then V = IR
When this equation fails and why cant we say that V=IR is the equation of resistance
Take example of the figure attached.
The first plot is of linear resistance, has constant slope throughout and hence constant resistance. The second image is that of a light bulb wire resistance. You can see its graph is not a straight line like the first one and comes under category of non linear resistance. No doubt V=IR applies on different points of the graph but the slopes at every point is different and hence resistance is different. So Ohm's law (i.e V proportional to I ) is valid but it cant be said equation to find resistance.
Hence assertion is true but the reason is incorrect.
Answer: c) Assertion is true, reason is incorrect.