Dual Nature of Radiation · Physics · WB JEE
MCQ (Single Correct Answer)
1
A beam of light of wavelength $$\lambda$$ falls on a metal having work function $$\phi$$ placed in a magnetic field B. The most energetic electrons, perpendicular to the field are bent in circular arcs of radius R. If the experiment is performed for different values of $$\lambda$$, then $$\mathrm{B}^2$$ vs. $$\frac{1}{\lambda}$$ graph will look like (keeping all other quantities constant)
WB JEE 2024
2
When light of frequency v1 is incident on a metal with work function W (where hv1 > W), then photocurrent falls to zero at a stopping potential of V1. If the frequency of light is increased to v2, the stopping potential changes to V2. Therefore, the charge of an electron is given by
WB JEE 2017
3
The potential difference V required for accelerating an electron to have the de-Broglie wavelength of 1 $$\mathop A\limits^o $$ is
WB JEE 2016
4
The work function of Cesium is 2.27 eV. The cut-off voltage which stops the emission of electrons from a cesium cathode irradiated with light of 600 nm wavelength is
WB JEE 2016
5
The number of de-Broglie wavelengths contained in the second Bohr orbit of hydrogen atom is
WB JEE 2016
MCQ (More than One Correct Answer)
1
Monochromatic light of wavelength $$\lambda=4770 \mathop A\limits^o $$ is incident separately on the surfaces of four different metals A, B, C and D. The work functions of A, B, C and D are $$4.2 \mathrm{~eV}, 3.7 \mathrm{~eV}, 3.2 \mathrm{~eV}$$ and $$2.3 \mathrm{~eV}$$, respectively. The metal / metals from which electrons will be emitted is / are
WB JEE 2024
2
Electric field component of an EM radiation varies with time as E = a (cos$$\omega$$0t + sin$$\omega$$t cos$$\omega$$0t), where a is a constant and $$\omega$$ = 1015 s$$-$$1, $$\omega$$0 = 5 $$\times$$ 1015 s$$-$$1. This radiation falls on a metal whose stopping potential is $$-$$2 eV. Then, which of the following statements is/are true ? (h = 6.62 $$\times$$ 10$$-$$34 J-s)
WB JEE 2021
3
A point source of light is used in an experiment of photoelectric effects. If the distance between the source and the photoelectric surface is doubled, which of the following may result?
WB JEE 2020
4
Electrons are emitted with kinetic energy T from a metal plate by an irradiation of light of intensity J and frequency v. Then, which of the following will be true?
WB JEE 2019
5
The distance between a light source and photoelectric cell is d. If the distance is decreased to $${d \over 2}$$, then
WB JEE 2016