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MODEL PAPER 10 — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsMODEL PAPER 101 Mark
MCQ
If $\mu_c$ and $\mu_h$ are electron and hole mobility, $E$ be the applied electric field, the current density $j$ for intrinsic semiconductor is equal to
  • ✓
    $n_i e\left(\mu_e+\mu_h\right) E$
  • B
    $\frac{n_i e\left(\mu_e+\mu_h\right)}{E}$
  • C
    $n_i e\left(\mu_e-\mu_h\right) E$
  • D
    $\frac{E}{n_i e\left(\mu_e+\mu_h\right)}$
✓

Answer

Correct option: A.
$n_i e\left(\mu_e+\mu_h\right) E$
$I = I _e+ I _{ h }$
$=e n_e A v_e+e n_h A v_h$
$=e A\left(n_e \mu_e+n_h \mu_h\right) E$
$j =\frac{I}{A}=e n_i\left(\mu_e+\mu_h\right) E$

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