If ${\mathrm{n}}_{\mathrm{e}}$ and ${\mathrm{v}}_{\mathrm{d}}$ be the number of electrons and drift velocity in a semiconductor. When the temperature is increased

(a) ${\mathrm{n}}_{\mathrm{e}}$ increases and ${\mathrm{v}}_{\mathrm{d}}$ decreases
(b) ${\mathrm{n}}_{\mathrm{e}}$ decreases and ${\mathrm{v}}_{\mathrm{d}}$ increases
(c) Both ${\mathrm{n}}_{\mathrm{e}}$ and ${\mathrm{v}}_{\mathrm{d}}$ increases
(d) Both ${\mathrm{n}}_{\mathrm{e}}$ and ${\mathrm{v}}_{\mathrm{d}}$ decreases

Concept Questions :-

Types of semiconductors
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The energy gap of silicon is 1.14 eV. The maximum wavelength at which silicon will begin absorbing energy is

(a) 10888 Å                    (b) 1088.8 Å
(c) 108.88 Å                   (d) 10.888 Å

Concept Questions :-

Energy band theory
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

Which of the following energy band diagram shows the N-type semiconductor

Concept Questions :-

Energy band theory
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

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

1. They carry negative charge

2. They are light

3. They mutually collide less

4. They require low energy to continue their motion

Concept Questions :-

Types of semiconductors
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

Which of the energy band diagrams shown in the figure corresponds to that of a semiconductor

Concept Questions :-

Energy band theory
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The energy band diagrams for three semiconductor samples of silicon are as shown. We can then assert that

(a) Sample X is undoped while samples Y and Z have been doped with a third group and a fifth group impurity respectively
(b) Sample X is undoped while both samples Y and Z have been doped with a fifth group impurity
(c) Sample X has been doped with equal amounts of third and fifth group impurities while samples Y and Z are undoped
(d) Sample X is undoped while samples Y and Z have been doped with a fifth group and a third group impurity respectively

Concept Questions :-

Energy band theory
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

In a semiconducting material, the mobilities of electrons and holes are ${\mathrm{\mu }}_{\mathrm{e}}$ and ${\mathrm{\mu }}_{\mathrm{h}}$ respectively. Which of the following is true?
(a) ${\mathrm{\mu }}_{\mathrm{e}}$>${\mathrm{\mu }}_{\mathrm{h}}$               (b)  ${\mathrm{\mu }}_{\mathrm{e}}$<${\mathrm{\mu }}_{\mathrm{h}}$
(c)  ${\mathrm{\mu }}_{\mathrm{e}}$${\mathrm{\mu }}_{\mathrm{h}}$             (d)  ${\mathrm{\mu }}_{\mathrm{e}}$<0; ${\mathrm{\mu }}_{\mathrm{h}}$>0

Concept Questions :-

Types of semiconductors
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The temperature (T) dependence of resistivity ($\rho$) of a semiconductor is represented by

Concept Questions :-

Types of semiconductors
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

In a forward biased PN-junction diode, the potential barrier in the depletion region is of the form

Concept Questions :-

PN junction
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Difficulty Level:

Different voltages are applied across a P-N junction and the currents are measured for each value. Which of the following graphs is obtained between voltage and current

Concept Questions :-

PN junction