The contribution in the total current flowing through a semicondu… - Vidyadip

MCQ

The contribution in the total current flowing through a semiconductor due to electrons and holes are $\frac{3}{4}$ and $\frac{1}{4}$ respectively. If the drift velocity of electrons is $\frac{5}{2}$ times that of holes at this temperature, then the ratio of concentration of electrons and holes is

✓
$6 : 5$
B
$5:6$
C
$3 : 2$
D
$2 : 3$

✓

Answer

Correct option: A.

$6 : 5$

a
(a)As we know current density $J = nqv$
==> ${J_e} = {n_e}q{v_e}$ and ${J_h} = {n_h}q{v_h}$
==> $\frac{{{J_e}}}{{{J_h}}} = \frac{{{n_e}}}{{{n_h}}} \times \frac{{{v_e}}}{{{v_h}}}$ ==> $\frac{{3/4}}{{1/4}} = \frac{{{n_e}}}{{{n_h}}} \times \frac{5}{{20}}$ ==> $\frac{{{n_e}}}{{{n_h}}} = \frac{6}{5}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q (1 Marks)" from 14. Semicondutor electronics→14. Semicondutor electronics — all question types→Physics STD 12 Science question papers→CBSE Board STD 12 Science question papers→CBSE Board question paper generator→

Similar questions

Two identical metal plates show photoelectric effect by a light of wavelength ${\lambda _A}$ falls on plate $A$ and ${\lambda _B}$ on plate $B$ $({\lambda _A} = 2{\lambda _B})$. The maximum kinetic energy is

The phase angle between current and voltage in a purely inductive circuit is:

Half life of radium is $1620$ years. How many radium nuclei decay in $5$ hours in $5\, gm$ radium? ( Atomic weight of radium $= 223$)

When the object is self-luminous, the resolving power of a microscope is given by the expression

A metallic sphere has a charge of $10\,\mu C$. A unit negative charge is brought from $A$ to $B$ both $100\,cm$ away from the sphere but $A$ being east of it while $B$ being on west. The net work done is........$joule$

$1 \,mg$ gold undergoes decay with $2.7$ days half-life period, amount left after $8.1$ days is ......... $mg$

Power delivered by the source of the circuit becomes maximum, when

In a $PN-$junction diode

In a circuit made up of resistance $4\,\Omega $ and inductance $0.01\, H$ , an alternating $emf$ $200\, V$ at $50\, Hz$ is connected, then the phase difference between the current and the $emf$ in the circuit is

An electron moves straight inside a charged parallel plate capacitor of uniform charge density. The space between the plates is filled with uniform magnetic field of intensity $B ,$ as shown in the figure, Neglecting effect of gravity, the time of straight line motion of the electron in the capacitor is