Resistance must be uniform
Current should be proportional to the size of the resistance
Resistance must be wire wound type
Temperature at positive end should be more than the temperature at negative end
Answer is Right!
Answer is Wrong!
The correct answer is: A. Resistance must be uniform.
Ohm’s law states that the current through a conductor between two points is directly proportional to the voltage across the two points, and inversely proportional to the resistance of the conductor.
In other words, if the voltage across a conductor is doubled, the current will also double. If the resistance of a conductor is doubled, the current will be halved.
For Ohm’s law to be valid, the resistance of the conductor must be uniform. This means that the resistance must be the same at all points along the conductor. If the resistance is not uniform, then the current will not be proportional to the voltage.
The other options are not necessary for Ohm’s law to be valid.
- Option B: Current should be proportional to the size of the resistance. This is not true. The current is proportional to the voltage, not the size of the resistance.
- Option C: Resistance must be wire wound type. This is not true. The resistance can be any type, as long as it is uniform.
- Option D: Temperature at positive end should be more than the temperature at negative end. This is not true. The temperature at the positive end and the negative end can be the same, or they can be different. The only important thing is that the resistance is uniform.