$A$ piece of copper and another of germanium are cooled from room temperature to $77 \ K$. The resistance of

The forbidden energy gap in the energy bands of germanium at room temperature is about $......$ $eV$.

The conductivity of a semiconductor increases with an increase in temperature because

Three semiconductors are arranged in the increasing order of their energy gap as follows. The correct arrangement is:

Carbon, silicon, and germanium atoms have four valence electrons each. Their valence and conduction bands are separated by energy band gaps represented by $(E_g)_C$, $(E_g)_{Si}$, and $(E_g)_{Ge}$ respectively. Which one of the following relationships is true in their case?

When the temperature of a silicon sample is increased from $27^\circ C$ to $100^\circ C$,the conductivity of silicon will be