Question

Consider the following statements. Which of the statements given is correct?

• A. Ohm's law is applicable to semiconductors.
• B. Ohm's law is not applicable at very low and very high temperatures.
• C. Conductance is the reciprocal of resistance and is measured in siemens.
• D. Ohm's law is not applicable to electron tubes, discharge tubes, and electrolytes.

Answer 1

Answer: (B), (C), (D)

Ohm's law is not applicable to electron tubes, discharge tubes, and electrolytes.

Ohm's law:

Ohm's law asserts that if all physical conditions and temperatures are unchanged, this same voltage across such a conductor is precisely proportional to the current flowing through all of it.

Mathematically, ohm's law can be represented as:

$\mathrm{V}=\mathrm{IR}$

or,

$\mathrm{I}=\frac{\mathrm{V}}{\mathrm{R}}$

or,

$\mathrm{R}=\frac{\mathrm{V}}{\mathrm{I}}$

Here,

R is the resistance.

V is the voltage.

I is the current.

The circuit diagram is below:

Ohm's law states that the slope of a V-I graph is a straight line, as in the case of conductors. However, with semiconductors, the slope of the V-I graph is curving rather than straight, meaning that Ohm's rule does not apply.

Therefore, options B, C, and D are correct.