Physics Of Solids Chapter 17 Physics 12th Class MCQ Test Preparation Punjab

Total Questions: 20

Total Marks: 20

Time: 20 Mins

Question # 1

What is the order of narrow forbidden energy gap between the conduction and valence bands of a semi-conductor?

1 eV
100 eV
5 eV
50 eV

Question # 2

Which of the following is an amorphous solid?

None of these
Silicon carbide
Quartz glass
Graphite

Question # 3

How can a magnet be demagnetized?

All of these
By heating it
By magnetizing it in opposite direction
By hammering it

Question # 4

What is the source of magnetism of an atom?

Positrons
Neutrons
Electrons
Protons

Question # 5

What happens to the material when the current is reduced to zero in the hysteresis loop?

The material doesn't retain magnetism
The material retains strong magnetism
The material retains weak magnetism
None of these

Question # 6

Why is graphite a good conductor of electricity?

It has valence electrons and it is a non-metallic form of carbon
It has valence electrons and it is a non-metallic form of carbon
It is a metal form of carbon
It is an allotropic form of carbon

Question # 7

Carbon, silicon and germanium have same lattice structure, then why carbon is insulator while silicon and germanium are semi conductors?

The presence of valence electrons in different orbits of carbon, silicon and germanium
The number of electrons in outer shells of these elements is different
Carbon, silicon and germanium are metals
None of these

Question # 8

Which of the following is a characteristic of amorphous solids?

Zero range order
None of these
Both short range order and indefinite heat of fusion
Long range order

Question # 9

How a certain region of space can be shielded from magnetic fields?

By surrounding the region using Bismuth
By surrounding the region using lithium
By surrounding the region using soft iron rings
None of these

Question # 10

Also what force would produce this stress if the diameter of the wire is 0.84 mm?

None of these

Question # 11

What is the purpose of doping in semiconductor?

To make the charge carriers move faster
To protect devices from damages
To give a semiconductor material certain properties
None of these

Question # 12

Why a ferrite core has less eddy current loss than an iron core?

Ferrites have high resistance
Ferrites have high hysteresis
Ferrites have low permeability
Ferrites are magnetic

Question # 13

A steel wire is loaded by a 2 kg mass. If the radius of wire is doubled, what will be its extension?

Double
None of these
One fourth
Half

Question # 14

SI unit of stress is same as that of which of the following quantities?

Pressure
Momentum
Force
Length

Question # 15

Which modulus determines the stretching of a coiled spring?

Young's modulus
Bulk modulus
Shear modulus
None of these

Question # 16

Which of the following is a characteristic of non-crystalline structures?

Well defined structure and geometry
Long range of periodicity
Low density
Sharp diffraction pattern

Question # 17

Why are amorphous solids referred as solid liquids?

Amorphous solids are more like solids with the disordered structure frozen in
Amorphous solids are more like liquids with the ordered structure frozen in
Amorphous solids are more like liquids with the disordered structure frozen in
Amorphous solids are more like liquids with the ordered structure in random motion

Question # 18

How can the deformation of a body occur?

By change in its length
By change in its area
By change in its volume
All of these

Question # 19

What is the impurity level in an extrinsic semiconductor as compared to that of a pure semiconductor?

1 atom for 108 atoms
1 atom for 100 atoms
1 atom for 104 atoms
10 atoms for 108 atoms

Question # 20

Why is glass known as solid liquid?

The molecules of glass are irregularly arranged as in a liquid but not fixed in their relative positions
The molecules of glass are periodically arranged as in a liquid but fixed in their relative positions
The molecules of glass are irregularly arranged as in a liquid but fixed in their relative positions
The molecules of glass are periodically arranged as in a liquid but not fixed in their relative positions