21.

The potential difference across a conductor of resistivity e is constant. The heat generated in the conductor is directly proportional to

• e

• $\frac{1}{\sqrt{\mathrm{e}}}$

• $\frac{1}{\mathrm{e}}$

• e²

The given logic symbol represents.

• AND gate

• OR gate

• NOT gate

• NAND gate

Which one of the following is not a conductor of electricity?

• Saltwater

• Distilled water

• Vinegar

• Lime juice

Which of the following process/processes destroy/destroys the magnetic properties of a bar magnet?

1. Cutting into two pieces
2. Heating
3. Beating
4. Sealing

• I, II and III

• I and IV

• Only I

• II and III

The common characteristic properties of plastics are

• durable, good conductor of electricity, non-reactive

• durable, good conductor of heat, non-reactive

• good conductor of heat, light in weight, a good conductor of electricity

• durable, light in weight, non-reactive

The current i flowing through the cell in the given circuit is (internal resistance of cell is zero)

• 1 A

• 3/2 A

• 2 A

• 3 A