Explore topic-wise MCQs in Testing Subject.

This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.

1.

The strongest force in the nature is

A. Electric force
B. Gravitational force
C. Nuclear force
D. Magnetic force
Answer» D. Magnetic force
2.

Which of the following has the longest de Broglie wavelength if they are moving with same velocity ?

A. Neutron
B. Proton
C. - particle
D. - particle
Answer» E.
3.

Nuclear fusion is the source of energy in

A. Sun and atom bomb
B. Nuclear reactor and sun
C. Sun and hydrogen bomb
D. Nuclear reactor and atom bomb
Answer» E.
4.

The matter waves are

A. e.m. waves
B. Sound waves
C. Mechanical waves
D. Probability waves
Answer» E.
5.

The velocity of photo electron emitted in photoelectric effect depends only on

A. The frequency and intensity of incident light
B. The frequency of inicdent light
C. Both (a) and (b)
D. The wave length of incident light
Answer» E.
6.

Heavy water is used as a moderator in a nuclear reactor. The function of the moderator is

A. To control the energy released in the reactor
B. To absorb neutrons and stop the chain reaction
C. To cool the reactor
D. To slow down the neutrons to thermal energy
Answer» E.
7.

Direct conversion of solar energy with the use of photovoltaic cell results in the production of

A. Optical energy
B. Electrical energy
C. Thermal energy
D. Mechanical energy
Answer» C. Thermal energy
8.

Nuclear forces are mediated by

A. Proton
B. Neutron
C. Meson
D. Electron
Answer» D. Electron
9.

Nuclear forces are

A. Spin dependent
B. Charge dependent
C. Long range
D. None of these
Answer» B. Charge dependent
10.

Photoelectric effect supports quantum nature of light because

A. There is a minimum frequency of light below which no photoelectrons are emitted
B. The maximum KE of photoelectrons depends only on the frequency of light and hot on its intensity
C. Even when the metal surface is faintly illuminated, the photoelectrons leave the surface immediately
D. Electric charge of the photoelectrons is quantised
Answer» B. The maximum KE of photoelectrons depends only on the frequency of light and hot on its intensity
11.

Out of the following, the one which can pass through 20 cm thickness of steel is

A. - rays
B. - rays
C. y - rays
D. ultraviolet rays
Answer» D. ultraviolet rays
12.

The colour of the + ve column in a gas discharge tube depends on

A. The type of glass used to construct the tube
B. The gas in the tube
C. The applied voltage
D. The material of the cathode
Answer» C. The applied voltage
13.

Which of the following is not the property of cathode rays ?

A. At produces heating effect
B. It does not deflect in electric field
C. Its casts shadow
D. It produces fluorescence
Answer» C. Its casts shadow
14.

The maximum number of photo electrons released in photocell is independent of

A. Nature of the cathode surface
B. Frequency of incident ray
C. Intensity of radiations incident on cathode surface
D. None of the above
Answer» C. Intensity of radiations incident on cathode surface
15.

When yellow light is incident on a surface no electrons are emitted while green light can emit. If red light is incident on the surface then

A. No electrons are emitted
B. Photons are emitted
C. Electrons of higher energy are emitted
D. Electrons of lower energy are emitted
Answer» B. Photons are emitted
16.

Particles which can be added to the nucleus of an atom without changing its chemical properties are

A. Electrons
B. Protons
C. Neutrons
D. -particles
Answer» D. -particles
17.

When the speed of electrons increases, then the value of the specific charge on an electron

A. Increases
B. Decreases
C. Remains unchanged
D. None of these
Answer» C. Remains unchanged
18.

The cause of fractional atomic weights of elements is the presence of

A. Isobars
B. Isotopes
C. isotones
D. None of these
Answer» C. isotones
19.

Which of the particles has similar mass to that of the electron ?

A. Proton
B. Neutron
C. Positron
D. Neutrino
Answer» D. Neutrino
20.

An atom bomb is based upon the principle of

A. Nuclear fission
B. Nuclear fusion
C. Controlled chain reaction
D. None of the above
Answer» B. Nuclear fusion
21.

In photoelectric effect, the number of photo electrons emitted is proportional to

A. Intensity of incident beam
B. Frequency of incident beam
C. Velocity of incident beam
D. Work function of photo cathode
Answer» B. Frequency of incident beam
22.

Which is the incorrect statement of the following ?

A. Photon is a particle with zero rest mass
B. Photon is a particle with zero momentum
C. Photon travels with velocity of light in vacuum
D. Photon even feel the pull of gravity
Answer» C. Photon travels with velocity of light in vacuum
23.

Alpha rays emitted from a radioactive substance are

A. Negatively charged particles
B. Hydrogen nuclear
C. Helium nuclear
D. None of the above
Answer» D. None of the above
24.

Which of the following will deflect in electric field ?

A. Y - rays
B. X - rays
C. Cathode rays
D. Ultraviolet rays
Answer» D. Ultraviolet rays
25.

Cathode rays are similar to visible light rays, in that

A. They both can be deflected by electric and magnetic fields
B. They both have a definite magnitude of wavelength
C. They both can ionise the gas through which they pass
D. They both can affect photographic plates
Answer» E.
26.

Isotopes have the same

A. Atomic number
B. Mass number
C. avogadro's number
D. None of these
Answer» B. Mass number
27.

The mass defect per nucleon is called

A. Binding energy
B. Packing fraction
C. Ionization energy
D. Excitation energy
Answer» C. Ionization energy
28.

The nuclear force

A. Obeys inverse square law of distance
B. Obeys inverse third power law of distance
C. Is a short range force
D. Is equal in strength to the electromagnetic force
Answer» D. Is equal in strength to the electromagnetic force
29.

Beta rays emitted by radioactive substance are

A. Electromagnetic radiations
B. Charged particles emitted by the nucleus
C. Electrons orbiting around the nucleus
D. None of the above
Answer» C. Electrons orbiting around the nucleus
30.

In nuclear reaction, there is conservation of

A. Mass only
B. Energy only
C. Momentum only
D. Mass energy and momentum
Answer» E.
31.

If alpha, beta and gamma rays carry same momentum, which has the longest wavelength ?

A. Alpha rays
B. Beta rays
C. Gamma rays
D. None, all have same wavelength
Answer» E.
32.

The dual nature of light is exhibited by

A. Diffraction and photoelectric effect
B. Diffraction and reflection
C. Refraction and interference
D. Photoelectric effect
Answer» B. Diffraction and reflection
33.

The wavelength of the matter waves is independent of

A. Charge
B. Momentum
C. Velocity
D. Mass
Answer» B. Momentum
34.

The main source of solar energy is

A. Nuclear fission
B. Nuclear fusion
C. Combustion
D. None of these
Answer» C. Combustion
35.

The important conclusion given by Millikan's experiment about the charge is

A. Charge is never quantized
B. Charges has no definite value
C. Charge is quantized
D. Charge on oil drop always increases
Answer» D. Charge on oil drop always increases
36.

Voltage applied between the electrodes of discharge tube is of the nature

A. 220 V alternating voltage
B. 220 V DC voltage
C. Variable voltage
D. Voltage obtained by induction coil
Answer» E.
37.

Hydrogen bomb is based upon the principle of

A. Nuclear fission
B. Nuclear fusion
C. Controlled nuclear fission
D. None of the above
Answer» C. Controlled nuclear fission
38.

The mass energy relation is the out come of

A. Quantum theory
B. General theory of relativity
C. Field theory of relativity
D. Special theory of relativity
Answer» E.
39.

Nuclear fission experiments show that the neutrons split the uranium nucleus into two fragments of about the same size. The process is accompanied by the emission of several

A. Protons and positrons
B. - particles
C. Neutrons
D. Protons and -particles
Answer» D. Protons and -particles
40.

In a discharge tube, ionization of enclosed gas is produced due to collisions between

A. Neutral gas atoms / molecules
B. Positive ions and neutral atoms / molecules
C. Negative electrons and neutral atoms / molecules
D. Photons and neutral atoms / molecules
Answer» D. Photons and neutral atoms / molecules
41.

The phenomenon of ejection of electrons from the surface of metals, when light of suitable wavelength falls on it, is known as

A. Electrolysis
B. Ionization
C. Photo electric effect
D. None of these
Answer» D. None of these
42.

Which of the following phenomena is observed when black discharge occurs in a discharge tube ?

A. The wall of the tube opposite to the cathode glow
B. Striations are seen
C. A glow appears at the cathode
D. Positive column appears
Answer» B. Striations are seen
43.

In a nuclear reactor, cadmium rods are used to

A. Speed up neutrons
B. Slow down neutrons
C. Absorb neutrons
D. Produce neutrons
Answer» D. Produce neutrons
44.

Cathode rays enter an electric field normal to the lines of force. Then their path in the electric field is

A. Straight line
B. Ellipse
C. Circle
D. Parabola
Answer» E.
45.

The ratio of specific charges of an - particle to that of a proton is

A. 1 / 3
B. 1 / 2
C. 1 / 1
D. 2 / 1
Answer» C. 1 / 1