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?

Number of electrons emitted ∝ J

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Ultraviolet radiation of 6.2 eV falls on an aluminium surface (work function 4.2 eV). The kinetic energy of the fastest electron emitted is approximately

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Important Questions on Dual Nature of Matter and Radiation

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IMPORTANT

Physics Crash Course JEE Advanced>Chapter 19 - Dual Nature of Matter and Radiation>Exercise 1>Q 15

Light of wavelength $2475 \overset{\circ}{A}$ is incident on barium. Photoelectrons emitted describe a circle of the radius $100 cm$ by a magnetic field of flux density $\frac{1}{\sqrt{17}} \times 10^{- 5} T$ . The work function of the barium is: (Given $\frac{e}{m} = 1.7 \times 10^{11} C {kg}^{- 1}$ .)

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Physics Crash Course JEE Advanced>Chapter 19 - Dual Nature of Matter and Radiation>Exercise 1>Q 16

In Davisson-Germer experiment, an electron beam of energy

60 eV

falls normally on the surface of a crystal. If the maximum intensity is obtained at an angle of

60^{\circ}

to the direction of incident beam, then the inter-atomic distance in the lattice plane of the crystal will be:

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Physics Crash Course JEE Advanced>Chapter 19 - Dual Nature of Matter and Radiation>Exercise 1>Q 17

When photons of energy

4.0 eV

fall on the surface of a metal

A

, the ejected photoelectrons have maximum kinetic energy

T_{A}

(in

eV

) and a de-Broglie wavelength

λ_{A}

. When the same photons fall on the surface of another metal

B

, the maximum kinetic energy of ejected photoelectrons is

T_{B} = T_{A} - 1 .5 eV

. If the de-Broglie wavelength of these photoelectrons is

λ_{B} = 2 λ_{A}

, then the work function of metal

B

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Physics Crash Course JEE Advanced>Chapter 19 - Dual Nature of Matter and Radiation>Exercise 1>Q 18

An electron in metal at

27 ° C

has a de-Broglie wavelength of ...

(Given m_{e} = 9 .1 \times 10^{- 31} kg, k_{B} = 1 .38 \times 10^{- 23} J K^{- 1})

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Physics Crash Course JEE Advanced>Chapter 19 - Dual Nature of Matter and Radiation>Exercise 1>Q 19

Photoelectric effect supports quantum nature of light because

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Physics Crash Course JEE Advanced>Chapter 19 - Dual Nature of Matter and Radiation>Exercise 1>Q 20

When a monochromatic point source of light is at a distance of

0.2 m

from a photoelectric cell, the cut-off voltage and the saturation current are respectively

0.6 V

and

18.0 mA

. If the same source is placed

0.6 m

away from the photocell, then :

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Physics Crash Course JEE Advanced>Chapter 19 - Dual Nature of Matter and Radiation>Exercise 1>Q 21

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?

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Physics Crash Course JEE Advanced>Chapter 19 - Dual Nature of Matter and Radiation>Exercise 1>Q 22

For photo-electric effect with incident photon wavelength

λ

, the stopping potential is

V_{0}

. Identify the correct variation(s) of

V_{0}

with

λ

and

\frac{1}{λ}

Ultraviolet radiation of 6.2 eV falls on an aluminium surface (work function 4.2 eV). The kinetic energy of the fastest electron emitted is approximately

Important Questions on Dual Nature of Matter and Radiation

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