The mobility of free electrons is greater than that of free holes because

Through a semiconductor,an electric current is due to the drift of

What will be the conductivity of a pure silicon crystal at $300 \ K$ temperature,if the electron-hole pairs per $cm^3$ is $1.072 \times 10^{10}$ at this temperature,$\mu_e = 1350 \ cm^2/V \cdot s$ and $\mu_h = 480 \ cm^2/V \cdot s$?

When $Ge$ crystals are doped with phosphorus atoms,then it becomes

In pure silicon at $300 \ K$ temperature,the concentration of electrons $n_e$ and holes $n_h$ is $1.5 \times 10^{16} \ m^{-3}$. By doping with Indium,$n_h$ is increased to $4.5 \times 10^{22} \ m^{-3}$. Calculate the concentration of electrons $n_e$ in the doped silicon.

When a battery is connected to a $P$-type semiconductor with a metallic wire,the current in the semiconductor (predominantly),inside the metallic wire,and inside the battery is due to which charge carriers respectively?