Dual Nature of Radiation · Physics · MHT CET

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MCQ (Single Correct Answer)

1

If the frequency of incident light in a photoelectric experiment is doubled, then stopping potential will

MHT CET 2025 25th April Evening Shift
2

An electron of mass ' $m$ ' and charge ' $e$ ' initially at rest gets accelerated by a constant electric field ' E '. The rate of change of de-Broglie wavelength of the electron at time ' $t$ ' is

(Ignore relativistic effect)( $\mathrm{h}=$ Planck's constant)

MHT CET 2025 25th April Evening Shift
3

If the electron in hydrogen atom jumps from third Bohr orbit to ground state directly and the difference between energies of the two states is radiated in the form of photons. If the work function of the material is 4.1 eV , then stopping potential is nearly

[Energy of electron in $n^{\text {th }}$ orbit $=\frac{-13 \cdot 6}{n^2} \mathrm{eV}$ ]

MHT CET 2025 25th April Morning Shift
4

When a metal surface is illuminated by light of wavelength $\lambda_1$ and $\lambda_2$, the maximum velocities of photoelectrons ejected are V and 2 V respectively. The work function of the metal is ( $\mathrm{h}=$ Planck's constant, $\mathrm{c}=$ velocity of light, $\lambda_1>\lambda_2$ )

MHT CET 2025 25th April Morning Shift
5
Sodium and copper have work functions 2.3 eV and 4.5 eV respectively. The ratio of threshold wavelength of sodium to that of copper is nearest to
MHT CET 2025 25th April Morning Shift
6

Graph shows variation of stopping potential with frequency of incident radiation on a metal plate. The value of Planck's constant is [ $\mathrm{e}=$ charge on photoelectron]

MHT CET 2025 23rd April Evening Shift Physics - Dual Nature of Radiation Question 3 English
MHT CET 2025 23rd April Evening Shift
7
Electron beam when accelerated by a voltage of 10 kV , has a de-Broglie wavelength ' $\lambda$ '. If the voltage is increased to 20 kV then the deBroglie wavelength associated with the electron beam would be
MHT CET 2025 23rd April Evening Shift
8

For two different photosensitive materials having work function $\phi$ and $2 \phi$ respectively, are illuminated with light of sufficient energy to emit electrons. If the graph of stopping potential versus frequency is drawn, for these two different photosensitive materials, the ratio of slope of graph for these two materials is

MHT CET 2025 23rd April Morning Shift
9

The energy that should be added to an electron to reduce its de-Broglie wavelength from $\lambda$ to $\frac{\lambda}{2}$ is $n$ times the initial energy. The value of ' $n$ ' is

MHT CET 2025 23rd April Morning Shift
10

When the electron orbiting in hydrogen atom goes from one orbit to another orbit (principal quantum number $=n$ ), the de-Broglie wavelength ( $\lambda$ ) associated with it is related to $n$ as

MHT CET 2025 22nd April Evening Shift
11

Photoelectric emission takes place from a certain metal at threshold frequency $v$. If the radiation of frequency $4 v$ is incident on the metal plate, the maximum velocity of the emitted photoelectrons will be ( $m=$ mass of photoelectron, $h=$ Planck's constant)

MHT CET 2025 22nd April Evening Shift
12

The de-Broglie wavelength of a neutron at $27^{\circ} \mathrm{C}$ is ' $\lambda_0$ '. What will be its wavelength at $927^{\circ} \mathrm{C}$ ?

MHT CET 2025 22nd April Evening Shift
13

When a photosensitive metal surface is illuminated with radiation of wavelength ' $\lambda_1$ ', the stopping potential is ' $\mathrm{V}_1$ '. If the same surface is illuminated with radiation of wavelength ' $3 \lambda_1$ ', the stopping potential is $\frac{\mathrm{V}_1}{6}$. The threshold wavelength for the photosensitive metal surface is

MHT CET 2025 22nd April Morning Shift
14

From photoelectric effect experiment, select the correct statement.

MHT CET 2025 22nd April Morning Shift
15

When photons of energies twice and thrice the work function of a metal are incident on the metal surface one after other, the maximum velocities of the photoelectrons emitted in the two cases are $V_1$ and $V_2$ respectively. The ratio $\mathrm{V}_1: \mathrm{V}_2$ is

MHT CET 2025 21st April Evening Shift
16

When a light of wavelength $\lambda$ falls on the emitter of a photocell, maximum speed of emitted photoelectrons is V . If the incident wavelength is changed to $\frac{2 \lambda}{3}$, maximum speed of emitted photoelectrons will be :

MHT CET 2025 21st April Evening Shift
17

The de-Broglie wavelength $(\lambda)$ of a particle

MHT CET 2025 21st April Morning Shift
18

Photoelectric emission is observed from a metallic surface for frequencies $v_1$ and $v_2$ of the incident light rays $\left(v_1>v_2\right)$. If the maximum values of kinetic energy of the photoelectrons emitted in the two cases are in the ratio of $1: \mathrm{k}$, then the threshold frequency of metallic surface is

MHT CET 2025 21st April Morning Shift
19

On a photosensitive material, when frequency of incident radiation is increased by $20 \%$, maximum kinetic energy of emitted photoelectrons increases from 0.4 eV to 0.7 eV . The work function of the material is

MHT CET 2025 20th April Evening Shift
20

A light of wavelength $\lambda$ is incident on a photosensitive surface of negligible work function. The photoelectrons emitted from the surface have de-Broglie wavelength $\lambda_1$. Then ratio $\lambda: \lambda_1{ }^2$ is

( $\mathrm{h}=$ Planck's constant, $\mathrm{c}=$ velocity of light, $\mathrm{m}=$ mass of electron)

MHT CET 2025 20th April Evening Shift
21

Light of wavelength ' $\lambda$ ' falls on a metal having work function $\frac{\mathrm{hc}}{\lambda_0}$. Photoelectric effect will take place only if ( $\lambda_0$ is the threshold wavelength)

MHT CET 2025 20th April Morning Shift
22

A parallel beam of light is incident normally on a plane surface absorbing $50 \%$ of the light and reflecting the rest. If the incident beam carries 90 W of power, the force exerted by it on the surface is ( $\mathrm{C}=$ velocity of light in air $=3 \times 10^8 \mathrm{~m} / \mathrm{s}$ )

MHT CET 2025 20th April Morning Shift
23

An electron accelerated by a potential difference ' $V$ ' has de-Broglie wavelength ' $\lambda$ '. If the electron is accelerated by a potential difference ' 9 V ', its de-Broglie wavelength will be

MHT CET 2025 19th April Evening Shift
24

The maximum velocity of the photoelectrons emitted by a metal surface is $9 \times 10^5 \mathrm{~m} / \mathrm{s}$. The value of ratio of charge (e) to mass (m) of the photoelectron is $1.8 \times 10^{11} \mathrm{C} / \mathrm{kg}$. The value of stopping potential in volt is

MHT CET 2025 19th April Evening Shift
25
Light of wavelength $\lambda$ strikes a photoelectric surface and electrons are ejected with energy E . If $E$ is to be increased to twice the original value, the wavelength changes to $\lambda_1$
MHT CET 2025 19th April Morning Shift
26
In a photoelectric experiment, if the intensity of incident light is doubled and the frequency is kept slightly greater than threshold frequency, then the saturation photoelectric current
MHT CET 2025 19th April Morning Shift
27

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 $\left(\frac{\lambda_1}{\lambda_2}\right) \propto E^n$ then the value of ' $n$ ' is

MHT CET 2024 16th May Evening Shift
28

A point source of light is used in a photoelectric effect. If the source is removed farther from the emitting metal, then the stopping potential will

MHT CET 2024 16th May Evening Shift
29

When an electron orbiting in hydrogen atom in its ground state jumps to higher excited state, the de-Broglie wavelength associated with it

MHT CET 2024 16th May Morning Shift
30

The figure shows the variation of photocurrent with anode potential for four different radiations. Let $\mathrm{I}_{\mathrm{a}}, \mathrm{I}_{\mathrm{b}}, \mathrm{I}_{\mathrm{c}}$ and $\mathrm{I}_{\mathrm{d}}$ be the intensities for the curves $a, b, c$ and $d$ respectively $\left[f_a, f_b, f_c\right.$ and $f_d$ are frequencies respectively]

MHT CET 2024 16th May Morning Shift Physics - Dual Nature of Radiation Question 29 English

MHT CET 2024 16th May Morning Shift
31

When a certain metallic surface is illuminated with monochromatic light wavelength $\lambda$, the stopping potential for photoelectric current is $4 \mathrm{~V}_0$. When the same surface is illuminated with light of wavelength $3 \lambda$, the stopping potential is $\mathrm{V}_0$. The threshold wavelength for this surface for photoelectric effect is

MHT CET 2024 15th May Evening Shift
32

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

MHT CET 2024 15th May Evening Shift Physics - Dual Nature of Radiation Question 31 English

MHT CET 2024 15th May Evening Shift
33

Two photons having energies twice and thrice the work function of metal are incident one after another on the metal surface. Then the ratio of maximum velocities of the photoelectrons emitted in the two cases is respectively

MHT CET 2024 15th May Morning Shift
34

Electrons are accelerated through a potential difference of 16 kV . If the potential difference is increased to 64 kV , then de-Broglie wavelength associated with electron will

MHT CET 2024 15th May Morning Shift
35

In case of photoelectric effect, the graph of measured stopping potential $\left(\mathrm{V}_0\right)$ against frequency ' $v$ ' of incident light is a straight line. The slope of this line multiplied by the charge of electron (e) gives

MHT CET 2024 11th May Evening Shift
36

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 $(\mathrm{h}=$ Planck's constant, $\mathrm{c}=$ speed of light $)$

MHT CET 2024 11th May Evening Shift
37

If the frequency of incident radiation $(\nu)$ is increased, keeping other factors constant, the stopping potential ( $\nu>\nu_0$, threshold frequency)

MHT CET 2024 11th May Morning Shift
38

If the potential difference used to accelerate electrons is doubled. By what factor does the deBroglie wavelength $(\lambda)$ associated with the electrons change?

MHT CET 2024 11th May Morning Shift
39

A photoelectric surface is illuminated successively by monochromatic light of wavelength ' $\lambda$ ' and $\left(\frac{\lambda}{2}\right)$. 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 ( $\mathrm{c}=$ speed of light, $\mathrm{h}=$ Planck's constant$)$

MHT CET 2024 10th May Evening Shift
40

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

MHT CET 2024 10th May Evening Shift
41

In photoelectric effect, the photocurrent

MHT CET 2024 10th May Morning Shift
42

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?

MHT CET 2024 10th May Morning Shift
43

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

MHT CET 2024 9th May Evening Shift Physics - Dual Nature of Radiation Question 44 English

MHT CET 2024 9th May Evening Shift
44

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

MHT CET 2024 9th May Evening Shift Physics - Dual Nature of Radiation Question 43 English

MHT CET 2024 9th May Evening Shift
45

The gyromagnetic ratio and Bohr magneton are given respectively by [Given $\rightarrow \mathrm{e}=$ charge on electron, $\mathrm{m}=$ mass of electron, $\mathrm{h}=$ Planck's constant]

MHT CET 2024 9th May Morning Shift
46

Two identical photocathodes receive light of frequencies ' $\mathrm{n}_1$ ' and ' $\mathrm{n}_2$ '. If the velocities of the emitted photoelectrons of mass ' $m$ ' are ' $\mathrm{V}_1$ ' and ' V , respectively, then ( $\mathrm{h}=$ Planck's constant )

MHT CET 2024 9th May Morning Shift
47

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

MHT CET 2024 4th May Evening Shift
48

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

MHT CET 2024 4th May Evening Shift
49

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 ' $\mathrm{V}_1$ '. When the frequency of incident radiation is increased to ' $5 \mathrm{~F}_0$ ', the maximum velocity of photoelectrons emitted is ' $V_2$ '. The ratio of $V_1$ to $V_2$ is

MHT CET 2024 4th May Morning Shift
50

For a photosensitive material, work function is ' $\mathrm{W}_0$ ' and stopping potential is ' V '. The wavelength of incident radiation is ( $\mathrm{h}=$ Planck's constant, $c=$ velocity of light, $e=$ electronic charge)

MHT CET 2024 4th May Morning Shift
51

The graph of stopping potential ' $\mathrm{V}_{\mathrm{s}}$ ' against frequency ' $v$ ' of incident radiation is plotted for two different metals ' X ' and ' Y ' as shown in graph. ' $\phi_x$ ' and ' $\phi_y$ ' are work functions of ' $x$ ' and ' $Y$ ' respectively then

MHT CET 2024 3rd May Evening Shift Physics - Dual Nature of Radiation Question 51 English

MHT CET 2024 3rd May Evening Shift
52

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

MHT CET 2024 3rd May Evening Shift
53

When the electron orbiting in hydrogen atom in its ground state moves to the third excited state, the de-Broglie wavelength associated with it

MHT CET 2024 3rd May Evening Shift
54

The ratio of the wavelength of a photon of energy ' $E$ ' to that of the electron of same energy is ( $\mathrm{m}=$ mass of an electron, $\mathrm{c}=$ speed of light, $\mathrm{h}=$ Planck's constant)

MHT CET 2024 3rd May Morning Shift
55

When photons of energy hv fall on a photosensitive surface of work function $\mathrm{E}_0$, photoelectrons of maximum energy $k$ are emitted. If the frequency of radiation is doubled the maximum kinetic energy will be equal to ( $\mathrm{h}=$ Planck's constant)

MHT CET 2024 3rd May Morning Shift
56

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

MHT CET 2024 2nd May Evening Shift
57

The stopping potential for a photelectric emission process is 10 V . The maximum kinetic energy of the electrons ejected in the process is [Charge on electron $\mathrm{e}=1.6 \times 10^{-19} \mathrm{C}$ ]

MHT CET 2024 2nd May Evening Shift
58

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 ' $\left(\frac{\mathrm{V}}{6}\right)$ '. The threshold wavelength for the surface is

MHT CET 2024 2nd May Morning Shift
59

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

MHT CET 2024 2nd May Morning Shift
60

When radiation of wavelength '$$\lambda$$' is incident on a metallic surface, the stopping potential is 4.8 V. If the surface is illuminated with radiation of double the wavelength then the stopping potential becomes $$1.6 \mathrm{~V}$$. The threshold wavelength for the surface is

MHT CET 2023 14th May Evening Shift
61

The de-Broglie wavelength $$(\lambda)$$ of a particle is related to its kinetic energy (E) as

MHT CET 2023 14th May Morning Shift
62

Dual nature of light is exhibited by

MHT CET 2023 13th May Evening Shift
63

When radiations of wavelength $$\lambda$$ is incident on a metallic surface the stopping potential required is $$4.8 \mathrm{~V}$$. If same surface is illuminated with radiations of double the wavelength, then required stopping potential becomes $$1.6 \mathrm{~V}$$, then the value of threshold wavelength for the surface is

MHT CET 2023 13th May Evening Shift
64

When a light of wavelength $$300 \mathrm{~nm}$$ fall on a photoelectric emitter, photo electrons are emitted. For another emitter light of wavelength $$600 \mathrm{~nm}$$ is just sufficient for liberating photoelectrons. The ratio of the work function of the two emitters is

MHT CET 2023 13th May Morning Shift
65

Light of frequency 1.5 times the threshold frequency is incident on photosensitive material. If the frequency is halved and intensity is doubled, the photocurrent becomes

MHT CET 2023 13th May Morning Shift
66

Graph shows the variation of de-Broglie wavelength $$(\lambda)$$ versus $$\frac{1}{\sqrt{V}}$$ where '$$V$$' is the accelerating potential for four particles A, B, C, D carrying same charge but of masses $$\mathrm{m_1, m_2, m_3, m_4}$$. Which on represents a particle of largest mass?

MHT CET 2023 12th May Evening Shift Physics - Dual Nature of Radiation Question 93 English

MHT CET 2023 12th May Evening Shift
67

When an electron is accelerated through a potential '$$V$$', the de-Broglie wavelength associated with it is '$$4 \lambda$$'. When the accelerating potential is increased to $$4 \mathrm{~V}$$, its wavelength will be

MHT CET 2023 12th May Evening Shift
68

Radiations of two photons having energies twice and five times the work function of metal are incident successively on metal surface. The ratio of the maximum velocity of photo electrons emitted in the two cases will be

MHT CET 2023 12th May Morning Shift
69

When light of wavelength $$\lambda$$ is incident on a photosensitive surface the stopping potential is '$$\mathrm{V}$$'. When light of wavelength $$3 \lambda$$ is incident on same surface the stopping potential is $$\frac{\mathrm{V}}{6}$$. Then the threshold wavelength for the surface is

MHT CET 2023 12th May Morning Shift
70

When a metallic surface is illuminated with radiation of wavelength '$$\lambda$$', the stopping potential is '$$\mathrm{V}$$'. If the same surface is illuminated with radiation of wavelength '$$2 \lambda$$', the stopping potential is '$$\left(\frac{\mathrm{v}}{4}\right)$$'. The threshold wavelength for the metallic surface is

MHT CET 2023 11th May Evening Shift
71

A metal surface of work function $$1 \cdot 13 \mathrm{~eV}$$ is irradiated with light of wavelength $$310 \mathrm{~nm}$$. The retarding potential required to stop the escape of photoelectrons is [Take $$\frac{\mathrm{hc}}{\mathrm{e}}=1240 \times 10^{-9} \mathrm{SI}$$ units]

MHT CET 2023 11th May Evening Shift
72

The maximum kinetic energies of photoelectrons emitted are $$\mathrm{K}_1$$ and $$\mathrm{K}_2$$ when lights of wavelengths $$\lambda_1$$ and $$\lambda_2$$ are incident on a metallic surface. If $$\lambda_1=3 \lambda_2$$ then

MHT CET 2023 11th May Morning Shift
73

If the potential difference used to accelerate electrons is doubled, by what factor does the de-Broglie wavelength associated with electrons change?

MHT CET 2023 10th May Evening Shift
74

The maximum kinetic energy of the photoelectrons varies

MHT CET 2023 10th May Evening Shift
75

An electron accelerated through a potential difference '$$V_1$$' has a de-Broglie wavelength '$$\lambda$$'. When the potential is changed to '$$V_2$$' its de-Broglie wavelength increases by $$50 \%$$. The value of $$\left(\frac{\mathrm{V}_1}{\mathrm{~V}_2}\right)$$ is

MHT CET 2023 10th May Morning Shift
76

Maximum kinetic energy of photon is '$$E$$' when wavelength of incident radiation is '$$\lambda$$'. If wavelength of incident radiations is reduced to $$\frac{\lambda}{3}$$ then energy of photon becomes four times. Then work function of the metal is

MHT CET 2023 10th May Morning Shift
77

When photons of energies twice and thrice the work function of a metal are incident on the metal surface one after other, the maximum velocities of the photoelectrons emitted in the two cases are $$\mathrm{v}_1$$ and $$\mathrm{v}_2$$ respectively. The ratio $$\mathrm{v}_1: \mathrm{v}_2$$ is

MHT CET 2023 9th May Evening Shift
78

When a certain metal surface is illuminated with light of frequency $$v$$, the stopping potential for photoelectric current is $$\mathrm{V}_0$$. When the same surface is illuminated by light of frequency $$\frac{v}{2}$$, the stopping potential is $$\frac{\mathrm{V}_0}{4}$$, the threshold frequency of photoelectric emission is

MHT CET 2023 9th May Evening Shift
79

From a metallic surface photoelectric emission is observed for frequencies $$v_1$$ and $$v_2\left(v_1 > v_2\right)$$ of the incident light. The maximum values of the kinetic energy of the photoelectrons emitted in the two cases are in the ratio $$1: \mathrm{x}$$. Hence the threshold frequency of the metallic surface is

MHT CET 2023 9th May Morning Shift
80

If the kinetic energy of a free electron doubles, it's de Broglie wavelength ($$\lambda$$) changes by a factor

MHT CET 2022 11th August Evening Shift
81

A light of wavelength '$$\lambda$$' and intensity '$$\mathrm{I}$$' falls on photosensitive material. If '$$\mathrm{N}$$' photo electrons are emitted, each with kinetic energy 'E', then

MHT CET 2021 24th September Evening Shift
82

In a photoelectric experiment, a graph of maximum kinetic energy $$(\mathrm{KE}_{\text {max }})$$ against the frequency of incident radiation (v) is plotted. If $$\mathrm{A}$$ and $$\mathrm{B}$$ are the intercepts on the $$\mathrm{X}$$ and $$\mathrm{Y}$$ axis respectively then the Planck's constant is given by

MHT CET 2021 24th September Evening Shift
83

A photon has wavelength $$3 \mathrm{~nm}$$, then its momentum and energy respectively will be $$[\mathrm{h}=6.63 \times 10^{-34} \mathrm{Js}, \mathrm{c}=$$ velocity of light $$=3 \times 10^8 \mathrm{~m} / \mathrm{s}]$$

MHT CET 2021 24th September Morning Shift
84

In photoelectric experiment keeping the frequency of incident radiation and accelerating potential fixed, if the intensity of incident light is increased,

MHT CET 2021 24th September Morning Shift
85

de-Broglie wavelength associated with an electron accelerated through a potential difference '$$\mathrm{V}$$' is '$$\lambda$$'. When the accelerating potential is increased to '$$4 \mathrm{~V}$$', de-Broglie wavelength.

MHT CET 2021 23rd September Evening Shift
86

In photoelectric effect, the photo current

MHT CET 2021 23rd September Evening Shift
87

According to de-Broglie hypothesis if an electron of mass '$$m$$' is accelerated by potential difference '$$V$$', the associated wavelength is '$$\lambda$$'. When a proton of mass '$$\mathrm{M}$$' is accelerated through potential difference $$9 \mathrm{~V}$$, then the wavelength associated with it is

MHT CET 2021 23rd September Evening Shift
88

When wavelength of incident radiation on the metal surface is reduced from '$$\lambda_1$$' to '$$\lambda_2$$', the kinetic energy of emitted photoelectrons is tripled. The work function of metal [$$\mathrm{h}=$$ Plank's constant, $$\mathrm{c}=$$ velocity of light]

MHT CET 2021 23th September Morning Shift
89

An electron of mass '$$m$$' and a photon have same energy '$$E$$'. The ratio of de-Broglie wavelength of electron to the wavelength of photon is $$(\mathrm{c}=$$ velocity of light)

MHT CET 2021 23th September Morning Shift
90

When a photon enters glass from air, which one of the following quantity does not change?

MHT CET 2021 22th September Evening Shift
91

The light of wavelength '$$\lambda$$' is incident on the surface of metal of work function $$\phi$$ and emits the electron. The maximum velocity of electron emitted is [$$\mathrm{m}=$$ mass of electron and $$\mathrm{h}=$$ Planck's constant, $$\mathrm{c}=$$ velocity of light]

MHT CET 2021 22th September Evening Shift
92

Photons of energy $$10 \mathrm{~eV}$$ are incident on a photosensitive surface of threshold frequency $$2 \times 10^{15} \mathrm{~Hz}$$. The kinetic energy in $$\mathrm{eV}$$ of the photoelectrons emitted is

[Planck's constant $$\mathrm{h}=6.63 \times 10^{34} \mathrm{~Js}$$ ]

MHT CET 2021 22th September Evening Shift
93

When a light of wavelength '$$\lambda$$' falls on the emitter of a photocells, maximum speed of emitted photoelectrons is '$$\mathrm{V}$$'. If the incident wavelength is changed to $$\frac{2 \lambda}{3}$$, maximum speed of emitted photoelectrons will be

MHT CET 2021 22th September Morning Shift
94

Kinetic energy of a proton is equal to energy '$$E$$' of a photon. Let '$$\lambda_1$$' be the de-Broglie wavelength of proton and '$$\lambda_2$$' is the wavelength of photon. If $$\frac{\lambda_1}{\lambda_2} \alpha E^n$$, then the value of '$$n$$' is

MHT CET 2021 22th September Morning Shift
95

The wave number of the last line of the Balmer series in the hydrogen spectrum will be $$\left(\right.$$ Rydberg's cons $$\left.\tan t, R=\frac{10^7}{\mathrm{~m}}\right)$$

MHT CET 2021 21th September Evening Shift
96

Photoemission from metal surface takes place for frequencies '$$v_1$$' and '$$v_2$$' of incident rays $$\left(v_1>v_2\right)$$. Maximum kinetic energy of photoelectrons emitted is in the ratio $$1: \mathrm{K}$$. The threshold frequency of metallic surface is

MHT CET 2021 21th September Evening Shift
97

A proton and alpha particle are accelerated through the same potential difference. The ratio of the de-Broglie wavelength of proton to that of alpha particle will be (mass of alpha particle is four times mass of proton.)

MHT CET 2021 21th September Evening Shift
98

Light of frequency two times the threshold frequency is incident on photosensitive material. If the incident frequency is made $$\left(\frac{1}{3}\right)^{\text {rd }}$$ and intensity is doubled, then the photoelectric current will

MHT CET 2021 21th September Morning Shift
99

On a photosensitive surface, if the intensity of incident radiation is increased, the stopping potential

MHT CET 2021 21th September Morning Shift
100

What is the additional energy that should be supplied to a moving electron to reduce its de Broglie wavelength from $$1 \mathrm{~nm}$$ to $$0.5 \mathrm{~nm}$$ ?

MHT CET 2021 20th September Evening Shift
101

Photoelectrons are emitted when photons of energy $$4.2 ~\mathrm{eV}$$ are incident on a photosensitive metallic sphere of radius $$10 \mathrm{~cm}$$ and work function $$2.4 ~\mathrm{eV}$$. The number of photoelectrons emitted before the emission is stopped is

$$\left[\frac{1}{4 \pi \epsilon_0}=9 \times 10^9\right.$$ SI unit; $$\left.\mathrm{e}=1.6 \times 10^{-19} \mathrm{C}\right]$$

MHT CET 2021 20th September Evening Shift
102

When light of wavelength '$$\lambda$$' is incident on a photosensitive surface, photons of power 'P' are emitted. The number of photon 'n' emitted in time 't' is [h = Planck's constant, c = velocity of light in vacuum]

MHT CET 2021 20th September Morning Shift
103

When a photosensitive surface is irradiated by light of wavelengths '$$\lambda_1$$' and '$$\lambda_2$$', kinetic energies of emitted photoelectrons are 'E$$_1$$' and 'E$$_2$$' respectively. The work function of photosensitive surface is

MHT CET 2021 20th September Morning Shift
104

The graph of stopping potential $V_s$ against frequency $v$ of incident radiation is plotted for two different metals $P$ and $Q$ as shown in the graph. $\phi_p$ and $\phi_Q$ are work-functions of $P$ and $Q$ respectively, then

MHT CET 2020 19th October Evening Shift Physics - Dual Nature of Radiation Question 65 English

MHT CET 2020 19th October Evening Shift
105

If the maximum kinetic energy of emitted electrons in photoelectric effect is $3.2 \times 10^{-19} \mathrm{~J}$ and the work-function for metal is $6.63 \times 10^{-19} \mathrm{~J}$, then stopping potential and threshold wavelength respectively are

[Planck's constant, $h=6.63 \times 10^{34} \mathrm{~J}$-s]

[Velocity of light, $c=3 \times 10^8 \frac{\mathrm{~m}}{\mathrm{~s}}$ ]

[Charge on electron $=1.6 \times 10^{-19} \mathrm{C}$ ]

MHT CET 2020 19th October Evening Shift
106

The light of wavelength $$\lambda$$ incident on the surface of metal having work function $$\phi$$ emits the electrons. The maximum velocity of electrons emitted is [ $$c=$$ velocity of light, $$h=$$ Planck's constant, $$m=$$ mass of electron]

MHT CET 2020 16th October Evening Shift
107

The graph of kinetic energy against the frequency $$v$$ of incident light is as shown in the figure. The slope of the graph and intercept on $$X$$-axis respectively are

MHT CET 2020 16th October Evening Shift Physics - Dual Nature of Radiation Question 67 English

MHT CET 2020 16th October Evening Shift
108

The maximum velocity of the photoelectron emitted by the metal surface is $$v$$. Charge and mass of the photoelectron is denoted by $$e$$ and $$m$$, respectively. The stopping potential in volt is

MHT CET 2020 16th October Morning Shift
109

Energy of the incident photon on the metal surface is $$3 W$$ and then $$5 W$$, where $$W$$ is the work function for that metal. The ratio of velocities of emitted photoelectrons is

MHT CET 2020 16th October Morning Shift
110

The stopping potential of the photoelectrons, from a photo cell is

MHT CET 2019 3rd May Morning Shift
111

When certain metal surface is illuminated with a light of wavelength $\lambda$, the stopping potential is $V$, When the same surface is illuminated by light of wavelength $2 \lambda$, the stopping potential is $\left(\frac{V}{3}\right)$. The threshold wavelength for the surface is

MHT CET 2019 3rd May Morning Shift
112

A metal surface is illuminated by light of given intensity and frequency to cause photoemission. If the intensity of illumination is reduced to one fourth of its original value then the maximum KE of the emitted photoelectrons would be

MHT CET 2019 2nd May Evening Shift
113

When photons of energy $h v$ fall on a metal plate of work function ' $W_0$ ', photoelectrons of maximum kinetic energy ' $K$ ' are ejected. If the frequency of the radiation is doubled, the maximum kinetic energy of the ejected photoelectrons will be

MHT CET 2019 2nd May Morning Shift
114

The maximum velocity of the photoelectron emitted by the metal surface is ' $v$ '. Charge and mass of the photoelectron is denoted by ' $e$ ' and ' $m$ ' respectively. The stopping potential in volt is

MHT CET 2019 2nd May Morning Shift
EXAM MAP