Mobilities of electrons and holes in a sample of a semiconductor is 25000 `cm^(2) V^(-1) s^(-1)` and 200 `cm^(2)` Vs respectively if the electron and hole concentration are `9 xx10^(13)` per `cm^(3)` and `4xx10^(12)` per `cm^(3)` respectively calculate the conductivity of the sample

Explanation

To calculate the conductivity of a semiconductor sample given the mobilities of electrons and holes, as well as their concentrations, we can follow these steps:

### Step 1: Write down the given values
- Mobility of electrons, \( \mu_e = 25000 \, \text{cm}^2/\text{V}\cdot\text{s} \)
- Mobility of holes, \( \mu_h = 200 \, \text{cm}^2/\text{V}\cdot\text{s} \)
- Electron concentration, \( n_e = 9 \times 10^{13} \, \text{cm}^{-3} \)
- Hole concentration, \( n_h = 4 \times 10^{12} \, \text{cm}^{-3} \)

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