Dual Nature of Radiation and Matter

Class 12 · Physics · 10 Questions

11.1intermediate🔧 Apply3 marksNumerical

Find the (a) maximum frequency, and (b) minimum wavelength of X-rays produced by 30 kV electrons.

11.2intermediate🔧 Apply5 marksNumerical

The work function of caesium metal is 2.14 eV. When light of frequency 6×6 \times 10^{14}$$ Hz is incident on the metal surface, photoemission of electrons occurs. What is the (a) maximum kinetic energy of the emitted electrons, (b) Stopping potential, and (c) maximum speed of the emitted photoelectrons?

11.3beginner🔧 Apply2 marksNumerical

The photoelectric cut-off voltage in a certain experiment is 1.5 V. What is the maximum kinetic energy of photoelectrons emitted?

11.4intermediate🔧 Apply5 marksNumerical

Monochromatic light of wavelength 632.8 nm is produced by a helium-neon laser. The power emitted is 9.42 mW. (a) Find the energy and momentum of each photon in the light beam, (b) How many photons per second, on the average, arrive at a target irradiated by this beam? (Assume the beam to have uniform cross-section which is less than the target area), and (c) How fast does a hydrogen atom have to travel in order to have the same momentum as that of the photon?

11.5intermediate🔧 Apply3 marksNumerical

In an experiment on photoelectric effect, the slope of the cut-off voltage versus frequency of incident light is found to be 4.12×4.12 \times 10^{-15}$$ Vs. Calculate the value of Planck's constant.

11.6intermediate🔧 Apply3 marksNumerical

The threshold frequency for a certain metal is 3.3×3.3 \times 10^{14} Hz. If light of frequency 8.2×8.2 \times 10^{14}$$ Hz is incident on the metal, predict the cut-off voltage for the photoelectric emission.

11.7intermediate🔧 Apply2 marksNumerical

The work function for a certain metal is 4.2 eV. Will this metal give photoelectric emission for incident radiation of wavelength 330 nm?

11.9intermediate🔧 Apply3 marksNumerical

Light of wavelength 488 nm is produced by an argon laser which is used in the photoelectric effect. When light from this spectral line is incident on the emitter, the stopping (cut-off) potential of photoelectrons is 0.38 V. Find the work function of the material from which the emitter is made.

11.10intermediate🔧 Apply4 marksNumerical

What is the de Broglie wavelength of (a) a bullet of mass 0.040 kg travelling at the speed of 1.0 km/s, (b) a ball of mass 0.060 kg moving at a speed of 1.0 m/s, and (c) a dust particle of mass 1.0×1.0 \times 10^{-9}$$ kg drifting with a speed of 2.2 m/s?

11.11intermediate💡 Understand3 marksLong Answer

Show that the wavelength of electromagnetic radiation is equal to the de Broglie wavelength of its quantum (photon).