Electric Conductivity

Step 1: Definition of an ideal battery.
An ideal battery is one that provides a constant potential difference (voltage) without any internal resistance. No energy is lost as heat, so no thermal energy is developed when charge flows through it.
Step 2: Analyze the options.
- Ideal dielectric: a material that doesn’t conduct charge.
- Ideal capacitor: a perfect capacitor with no losses or imperfections.
- Ideal resistor: a resistor with no internal heat dissipation (not possible in real life).
Step 3: Conclusion.
The battery that does not develop any thermal energy when charge flows through it is called an ideal battery.
Final Answer:

Step 1: Superconductivity properties.
Superconductors exhibit several unique behaviors when cooled below their critical temperature: - Meissner Effect: Expulsion of magnetic fields from a superconductor. - Formation of Cooper pairs: Electrons pair up with opposite spin and momentum, enabling superconductivity. - Zero resistivity: Complete absence of electrical resistance. Step 2: Paramagnetism.
- Paramagnetism: Materials that are weakly attracted by an external magnetic field, which is not a property of superconductors. Instead, superconductors are characterized by perfect diamagnetism (expelling the magnetic field).
Final Answer:

Step 1: Relation between conductivity and resistivity.
Conductivity ( ) is reciprocal of resistivity ( ): Step 2: Dimensions of resistivity.
Resistivity: where resistance . Voltage ( ) has dimensions: Current ( ) = [A]. So, Now, Step 3: Conductivity.

Final Answer: