MHT-CET PYQs 2024 - Physics: Dual Nature of Radiation & Matter

Dual Nature of Radiation and Matter

2.  If the frequency of incident radiation ($v$) is increased, keeping other factors constant, the stopping potential (v > $v_0$, threshold frequency)

3.  The number of photoelectrons emitted for light of frequency $v$ (higher than the threshold frequency ( $v_0$ ) is proportional to

4. In photoelectric effect, the photocurrent

5. Calculate wave length for emission of a photon having wave number $11516$ $c{m}^{-1}$.

6. For a photosensitive material, work function is ‘$W_0$’ and stopping potential is ‘$V$’. The wavelength of incident radiation is ($h$ = Planck’s constant, $c$ = velocity of light, $e$ = electronic charge) 

7. The frequency of incident light falling on a photosensitive material is doubled, the K.E. of the emitted photoelectrons will be

8.  When photons of energy $hv$ fall on a photosensitive surface of work function  $E_0$, photoelectrons of maximum energy $k$ are emitted. If the frequency of radiation is doubled the maximum kinetic energy will be equal to ($h$ = Planck’s constant)

9. Using Einstein’s photoelectric equation, the graph between kinetic energy of emitted photoelectrons and the frequency of incident radiation is shown correctly by graph :

10. The graph of stopping potential ‘$V_s$’ against frequency ‘$v$’ of incident radiation is plotted for two different metals ‘$X$’ and ‘$Y$’ as shown in graph. ‘${\mathrm{\Phi }}_x$’ and ‘${\mathrm{\Phi }}_y$’ are work functions of ‘$X$’ and ‘$Y$’ respectively then

11. In case of photoelectric effect, the graph of measured stopping potential ($V_0$) against frequency ‘$v$’ of incident light is a straight line. The slope of this line multiplied by the charge of electron ($e$) gives

12.  The stopping potential as a function of frequency of incident radiation is plotted for two different photoelectric surfaces $A$ and $B$. The graph shows that the work function of $A$ is

13. The figure shows the variation of photocurrent with anode potential for four different radiations. Let $f_a$, $f_b$, $f_c$ and $f_d$ be the frequencies for the curves $a$, $b$, $c$ and $d$ respectively

14. The figure shows the variation of photocurrent with anode potential for four different radiations. Let $I_a$, $I_b$, $I_c$ and $I_d$ be the intensities for the curves $a$, $b$, $c$ and $d$ respectively. Then [$f_a$, $f_b$, $f_c$ and $f_d$ are frequencies respectively]

15.  When a photosensitive surface is irradiated by lights of wavelengths '${\lambda }_1$' and ‘${\lambda }_2$’, kinetic energies of the emitted photoelectrons is ‘$E_1$’ and ‘$E_2$’ respectively. The work function of the photosensitive surface is

16. Two identical photocathodes receive light of frequencies ‘$n_1$’ and ‘$n_2$’. If the velocities of the emitted photoelectrons of mass ‘$m$’ are ‘$V_1$’ and ‘$V_2$’ respectively, then ($h$ = Planck’s constant)

17.  The work function of metal ‘$A$’ and ‘$B$’ are in the ratio $1:2$. If light of frequency ‘$f$’ and ‘$2f$’ is incident on surface ‘$A$’ and ‘$B$’ respectively, then the ratio of kinetic energies of emitted photo electrons is

18.  A photoelectric surface is illuminated successively by monochromatic light of wavelength $\lambda$ and ($\lambda$/$3$). If the maximum kinetic energy of the emitted photoelectrons in the second case is 4 times that in the first case, the work function of the surface of the material is ($h$ = Planck’s constant, $c$ = speed of light)

19.  A photoelectric surface is illuminated successively by monochromatic light of wavelength ‘$\lambda$’ and ($\frac{\lambda }{2}$ ) . If the maximum kinetic energy of the emitted photoelectrons in the first case is one-fourth that in the second case, the work function of the surface of the material is ($c$ = speed of light, $h$ = Planck’s constant)

20.  When a metallic surface is illuminated with a radiation of wavelength ‘$\lambda$’, the stopping potential is ‘$V$’. If the same surface is illuminated with radiation of wavelength ‘$3\lambda$’, the stopping potential is ($\frac{V}{6}$ ). The threshold wavelength for the surface is

21.  When a certain metallic surface is illuminated with monochromatic light wavelength $\lambda$, the stopping potential for photoelectric current is $4$$V_0$. When the same surface is illuminated with light of wavelength $3\lambda$, the stopping potential is $V_0$. The threshold wavelength for this surface for photoelectric effect is 

22. The threshold frequency of a metal is ‘$F_0$’. When light of frequency $2$$F_0$ is incident on the metal plate, the maximum velocity of photoelectron is ‘$V_1$’. When the frequency of incident radiation is increased to ‘$5$ $F_0$’, the maximum velocity of photoelectrons emitted is ‘$V_2$’. The ratio of $V_1$ and $V_2$ is 

23. A photosensitive metallic surface has work function $\mathrm{\Phi }$. If photon of energy $3\mathrm{\Phi }$ falls on the surface, the electron comes out with a maximum velocity of $6$ × ${10}^6$ m/s. When the photon energy is increased to $9\mathrm{\Phi }$, then maximum velocity of photoelectrons will be

24. The kinetic energy of an electron is increased by $2$ times, then the de-Broglie wavelength associated with it changes by a factor

25.  If the potential difference used to accelerate electrons is doubled, by what factor does the de-Broglie wavelength ($\lambda$) associated with the electrons change?

26. If the potential difference used to accelerate electrons is increased four times, by what factor does the de-Broglie wavelength associated with the electrons change?

27.  The ratio of the wavelength of a photon of energy $E$ to that of the electron of same energy is ($m$ = mass of an electron, $c$ = speed of light, $h$ = Planck’s constant)

28.  Kinetic energy of a proton is equal to energy $E$ of a photon. Let ' ${\lambda }_1$ ' be the de-Broglie wavelength of proton and ' ${\lambda }_2$ ' be the wavelength of photon. If $(\frac{{\lambda }_1}{{\lambda }_2})\alpha E^n$ , then the value of $n$ is