R4RIN – MCQs, Mock Tests | NCERT Class 12 MCQ Questions for Class 12 Physics Chapter 11 Dual Nature of Radiation and Matter

De-Broglie equation states the:

1. dual nature
2. particle nature
3. wave nature
4. None of the these

✅ Correct Answer: 1

Protons and alpha particles have the same de-Broglie wavelength. What is same for both of them ?

1. Energy
2. Time period
3. Frequency
4. Momentum

✅ Correct Answer: 4

Kinetic energy of emitted electrons depends upon :

1. frequency
2. intensity
3. nature of atmosphere surrounding the electrons
4. None of the above

✅ Correct Answer: 1

The ratio of specific charge of an alpha particle to the proton is:

1. 1 : 2
2. 2 : 1
3. 4 : 1
4. 1 : 4

✅ Correct Answer: 1

In Thomson’s experiment number of parabola gives :

1. the no. of electrons present in element
2. the no. of proton present in element
3. the no. of neutrons present in element
4. the no. of isotopes of the element present

✅ Correct Answer: 4

The work function of photoelectric material is 3.3 eV. The threshold frequency will be equal to:

1. 8 × 1014 Hz
2. 8 × 1010 Hz
3. 5 × 1010 Hz
4. 4 × 1014 Hz

✅ Correct Answer: 1

The strength of photoelectric current depends upon :

1. angle of incident radiation
2. frequency of incident radiation
3. intensity of incident radiation
4. distance between anode and cathode

✅ Correct Answer: 2

The momentum of an electron that emits a wavelength of 2 Å. will be:

1. 6.4 × 10-36 kgms-1
2. 3.3 × 10-24 kgms-1
3. 3.3 × 10-34 kgms-1
4. none of these

✅ Correct Answer: 2

Name the scientists who first studied the passage of electricity through fluids to establish the electrical nature of matter:

1. Millikan
2. Planck
3. Faraday
4. Boyle

✅ Correct Answer: 3

Millikan’s oil drop experiment makes use of:

1. Stokes’ law
2. Boyle’s law
3. Gas equation
4. Bernoulli’s theorem

✅ Correct Answer: 1

X-rays are:

1. deflected by an electric field
2. deflected by a magnetic field
3. deflected by both electric and magnetic fields
4. not deflected by electric and magnetic fields

✅ Correct Answer: 4

In photo electric emission, for alkali metals the threshold frequency lies in the:

1. visible region
2. ultraviolet region
3. infrared region
4. far end of the infrared region

✅ Correct Answer: 1

Which of the following radiations cannot eject photo electrons?

1. ultraviolet
2. infrared
3. visible
4. X-rays

✅ Correct Answer: 2

What is the de-Broglie wavelength of an electron accelerated from rest through a potential difference of 100 volts?

1. 12.3 Å
2. 1.23 Å
3. 0.123 Å
4. None of the these

✅ Correct Answer: 2

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

1. no electrons are emitted
2. photons are emitted
3. electrons of higher energy are emitted
4. electrons of lower energy are emitted

✅ Correct Answer: 1

The de-Broglie wavelength of particle of mass 1 mg moving with a velocity of 1 ms-1, in terms of Planck’s constant h, is given by (in metre):

1. 105 h
2. 106 h
3. 10-3 h
4. 103 h

✅ Correct Answer: 2

Evidence of the wave nature of light cannot be obtained from:

1. diffraction
2. interference
3. doppler effect
4. reflection

✅ Correct Answer: 4

which Characteristic of a target does the Mosley’s law relate the frequency of X-rays?

1. density
2. atomic number
3. atomic weight
4. interatomic space

✅ Correct Answer: 2

Compared to liquids and solids, gases are:

1. good conductors of electricity
2. best conductors of electricity
3. very poor conductors of electricity
4. good or bad conductors of electricity depending upon the nature of the gas

✅ Correct Answer: 3

The different stages of discharge in a discharge tube can be explained on the basis of:

1. the wave nature of light
2. the dual nature of light
3. wave nature of electrons
4. the collision between the charged particles emitted from the cathode the atoms of the gas in the tube

✅ Correct Answer: 4