Explain with the help of band theory why a semiconductor is neither a good conductor nor a good insulator.

What is good conductor of heat?

Write the name of a good conductor.

What is good conductors and bad conductors of heat?

Explain the electrical conductivity of a semiconductor with the help of band theory.

Write down the difference between conductor semiconductor and insulator.

Good conductor of electricity is/are

Name a liquif which is a good conductor of heat.

Two long straight parallel conducts carrying steady currents I_(1) and I_(2) are separated by a distance d. Explain briefly with the help of suitable diagram, how the magnetic field due to one conductor acts on the other. Hence deduce the expression for the force acting between the two conductors. Mention the nature of this force.

Explain why the alkaline earth metals are good conductor of heat and electricity.