NCERT Class11 NEET IIT JEE,CBSE Modern physics MCQs,PDFs,Tests

# Modern Physics Mock Test-2

The momentum of a photon is 3.3X10-29kg-m/s. Its frequency will be

[A] 3 x103Hz
[B] 6×103Hz
[C] 7.5×1012Hz
[D] 1.5×1013Hz

The momentum of a photon is 2×10-16 g-cm /s. Its energy is

[A] 0.61×10-26 erg
[B] 2.0×10-26 erg
[C] 6×10-6erg
[D] 6×10-8 erg

The rest mass of photon is

[A] zero
[B] infinity
[C] between 0 and infinity
[D] equal to that of an electron

The momentum of the photon of wavelength 5000 Å will be

[A] 1.3×10-27 kg-m/s
[B] 1.3×10-28 kg-m/s
[C] 4×10-29 kg-m/s
[D] 4×10-18kg-m/s

A photon in motion has a mass

[A] $$\frac{c}{hν}$$

[B] $$\frac{ν}{h}$$

[C] hν

[D] $$\frac{hν}{c^2}$$

The approximate wavelength of aphoton of energy 2.48 eV

[A] 500Å
[B] 5000Å
[C] 2000Å
[D] 1000Å

The number of photons of wavelength 540 nm emitted per second by an electric bulb of power 100 W is (taking h =6×10-34J-s)

[A] 100
[B] 1000
[C] 3×1020
[D] 3×1018

If the energy of the photon is increased by a factor of 4, then its momentum

[A] does not change
[B] decreases by a factor of 4
[C] increases by a factor of 4
[D] increases by a factor of 2

Which of one is correct?

[A] E2 = p2c2
[B] E2 = p2c
[C] E2 = pc2
[D] E2 = p2/c2

The energy of incident photons corresponding to maximum wavelength of visible light is

[A] 3.2 eV
[B] 7 eV
[C] 1.75eV
[D] 1 eV

The momentum of a photon is 6.6x 10-29 kg- ms-1. The frequency of the radiation (in Hz) is

[A] 3×1013
[B] 3×108
[C] 3×1015
[D] 3×106

The number of photons of wavelength 540 nm emitted per second by an electric bulb of power 100 W is approximately (taking h = 6×10-34 J-s)

[A] 4×1016
[B] 4×1010
[C] 3×1020
[D] 3×1018

Two photons having

[A] equal wavelengths have equal linear momenta
[B] equal energies have equal linear momenta
[C] equal frequencies have equal linear momenta
[D] All of the above

Let p and E denote the linear momentum and energy of a photon. If the wavelength is decreased, then

[A] Both p and E increase
[B] p increases and E decreases
[C] p decreases and E increases
[D] Both p and E decrease

For the Bohr’s first orbit of circumference 2πr, the de-Broglie wavelength of revolving electron will be

[A] 2πr

[B] πr

[C] $$\frac{1}{2πr}$$

[D] $$\frac{1}{4πr}$$

In the nth orbit, the energy of an electron En=-$$\frac{13.6}{n^2}$$ eV for hydrogen atom. The energy required to take the electron from first orbit to second orbit will be

[B] 12.1 eV
[C] 13.6 eV
[D] 3.4eV

Which one of the series of hydrogen spectrum is in the visible region?

[A] Lyman series
[B] Balmer series
[C] Paschen series
[D] Bracket series

lonization potential of hydrogen atom is 13.6 V. Hydrogen atoms in the ground state are excited by monochromatic radiation of photon energy 12.1 eV. The spectral lines emitted by hydrogen atoms [A] One
[B] Two
[C] Three
[D] Four