Question

Which of the following is true regarding electrical conductivity of metals and semiconductors?

• A. On increasing the temperature, electrical conductivity of metals increases, while that of semiconductor decreases.
• B. On increasing the temperature, electrical conductivity of metals decreases, while that of semiconductor increases.
• C. Electrical conductivity of both metals and semiconductors increases on increasing temperature.
• D. Electrical conductivity of both metals and semiconductors decreases on increasing temperature.

Answer 1

The correct option is B On increasing the temperature, electrical conductivity of metals decreases, while that of semiconductor increases.

The conduction of electricity for semiconductors depends on the temperature as follows:
At higher temperature, some electrons are thermally excited from the valence band to the conduction band. So, their electrical conductivity will increase with a rise in the temperature.

The conductivity of metal (conductors) decreases with increase in temperature resulting in the decrease in current flow and metal conductivity.

Also, the conductivity of insulators increase with an increase in temperature.