Modern Physics: MCQ Test (25 questions)

Question 1 of 25

Photovoltaic cells are-

ASolar Cell
BThermal Cell
CSulfur Cell
Dmolar cell

Question 2 of 25

Which one of the following is essential in the construction of a nuclear reactor?

ACobalt
BNickel
CZirconium
Dtungsten

Question 3 of 25

Isotopes are atoms of the same element that have

ASame atomic weight but different atomic number
BDifferent atomic weights but same atomic number
CBoth atomic mass and atomic number are the same.
Dnone of the above

Question 4 of 25

Laser beam is used for-

ALaser beam is used
Bin cardiac medicine
Cin eye medicine
DIn kidney therapy

Question 5 of 25

The following principle works in the atomic bomb:

Anuclear fusion
Bnuclear fission
CFleming's Law
Dphotoelectric effect

Question 6 of 25

Heavy water (D) in nuclear reactors2In what form is O used?

Adiluent
Bcoolant
Cpreservative
Dcontroller

Question 7 of 25

The first nuclear reactor was built by-

AEinstein
BNewton
CRutherford
DFermi

Question 8 of 25

Stars obtain their energy from- 1. Nuclear fusion 2. Gravitational contraction 3. Chemical reaction 4. Nuclear fission

A1 and 2
B1, 2 and 3
C1 and 4
D2 and 4

Question 9 of 25

In isotopic atoms-

Ahave the same number of protons
Bhave the same number of neutrons
Chave the same number of nucleons
DAll are true

Question 10 of 25

Which of the following is used as a coolant in the Fast Breeder Test Reactor at Kalpakkam?

Acarbon dioxide
Bheavy water
Csea water
Dmolten sodium

Question 11 of 25

What is radar used for?

Adetection of submerged submarines
BReceiving signals from a radio receiver
CIdentifying distant objects and detecting energy
Dlocating the satellite

Question 12 of 25

The phenomenon associated with forming a three-dimensional image by the interference of two light rays emanating from a laser or any other coherent light source is called –

Aoptical photography
BX-ray photography
CRadiation Illustration
DHolography

Question 13 of 25

What is the conductivity of a superconductor?

AUnlimited
BLess
CZero
DMore

Question 14 of 25

Which of the following metals is used as a semiconductor in transistors?

ACopper
BGermanium
Cgraphite
DSilver

Question 15 of 25

Otto Hahn discovered the atomic bomb on the basis of the following principle:

Auranium fission
Bnuclear fission
Calpha radiation
Dgamma radiation

Question 16 of 25

What is the Coolidge tube used to produce?

Aradio waves
Bmicrowaves
CX-rays
Dgamma rays

Question 17 of 25

In a laser, all the atoms emit light waves.

Aof the same frequency
Bof the same dimension
Cof the same phase
DAll of the above

Question 18 of 25

Diode is a device which allows current to

Aallows flow in one direction
BAllows flow in both directions
CDoes not allow flow in any direction
Dnone of the above

Question 19 of 25

Find the number of protons in the nucleus of a hydrogen atom.

AZero
BOne
CThree
Dfive

Question 20 of 25

The atomic number of an element is the number of...

Aneutrons in the nucleus
Belectrons in the nucleus
Cprotons in the nucleus
Dnone of these

Question 21 of 25

The nucleus of an atom contains-

Aprotons and electrons
Bneutrons and electrons
Cjust electrons
Dneutrons and electrons

Question 22 of 25

X-rays are used to study crystal structure because-

AThe crystal completely absorbs X-rays.
BThe wavelength of X-rays and the interatomic distance of the crystal are of the same order of magnitude.
CX-rays have very small wavelengths, comparable to the interatomic distances of a crystal.
DThe crystal is completely transparent to X-rays.

Question 23 of 25

A beam of light which is highly directional is called-

AEraser
BGrazer
CMesser
DLaser

Question 24 of 25

Barium is fed to patients in a suitable form before abdominal X-ray examination because-

ABarium allows X-rays to pass through the stomach due to its transparency to X-rays.
BVarium compounds, like magnesium sulfate, help clear the stomach before X-ray examinations.
CBarium is a good absorber of X-rays and this helps the stomach (compared to other areas) to be seen more clearly in the image.
DBarium salts are white in color and this helps the stomach to be seen more clearly in the image than other areas.

Question 25 of 25

Energy is produced in nuclear reactors by-

Aby controlled fusion
Bby uncontrolled fusion
Cby controlled fission
Dby uncontrolled fission