Dual Nature of Radiation and Matter Mock Test – Class 12 Physics

1. Use the arrangement described below.

In this arrangement, plate is mainly used to

2. Assertion: Saturation current in the photoelectric effect depends on the intensity of incident radiation when the frequency is above threshold.
Reason: At saturation, the current is limited by the number of photoelectrons emitted per second.

3. From a photoelectric surface of work function , light ejects fastest electrons that are then treated using de Broglie wavelength. Taking , , , and , the de Broglie wavelength of the fastest photoelectrons is closest to

4. In electron emission from a metal, the term “surface phenomenon” is most appropriate because

5. A quantity has the unit . In dual-nature calculations, it is most naturally identified as

6. A table from a photoelectric current experiment is shown below.

Which assessment is appropriate?

7. For fixed frequency above threshold, the graph between saturation current and light intensity is expected to be

8. A summary table is shown below.

The row that does not fit the conclusions about dual nature is

9. For a threshold wavelength of , light of wavelength falls on the metal. Using , the maximum kinetic energy is closest to

10. A data table for two above-threshold beams falling on the same metal area is shown below.

The missing photon rates for and are respectively

11. For electromagnetic radiation in vacuum, the graph of photon energy against wavelength should show that

12. For radiation of fixed frequency , increasing the intensity mainly means that

13. The same photoelectric surface is illuminated first by radiation of frequency and then by radiation of frequency . If , the increase in stopping potential is closest to

14. An electron needs to just escape from a metal surface. Express this minimum escape energy in . Use .

15. An electron and a proton have the same speed , while another electron has speed . Which arrangement of de Broglie wavelengths is correct?

16. Which quantity represents the energy gained by a charge when it moves through a potential difference ?

17. Heisenberg’s uncertainty idea is connected with wave-particle duality because a microscopic particle described by a wave packet cannot generally have

18. The SI unit of Planck’s constant can be written as

19. The work function of a metal is . If , the threshold frequency is

20. A comparison of frequency effects is shown below.

The assessment of the table is

21. Under above-threshold illumination, a photoelectric tube gives at a high positive collector potential, and no further increase is observed when the potential is raised. The number of photoelectrons emitted per second is approximately

22. Two metals have threshold wavelengths and . Their work functions satisfy

23. In a Davisson-Germer type setup, a detector peak shifts to a smaller Bragg angle when the accelerating voltage is increased. The shift is consistent with

24. Given work function and stopping potential for the incident radiation, the photon energy is

25. The negative-side potential-axis intercept of a photoelectric current-potential graph for fixed above-threshold frequency gives

26. The pair of observations that most directly shows the two complementary halves of dual nature is

27. Two particles have the same kinetic energy , but particle has mass and particle has mass . Their non-relativistic de Broglie wavelengths satisfy

28. For a metal of work function illuminated by light, use . The stopping potential is closest to

29. Match the electron-emission type with its immediate physical cause.

The correct matching is

30. For a photon of wavelength , taking , its momentum is approximately

31. In an arrangement, a metal plate is connected to an external circuit in vacuum and illuminated by suitable radiation. Electrons leave the illuminated surface and move toward a collecting electrode. The emitted electrons are called

32. A positively charged metal plate in a simple Hallwachs observation does not show the same discharge when ultraviolet light falls on it. The most suitable reason is that

33. A photon has wavelength . An electron also has de Broglie wavelength . The photon energy is , while the electron kinetic energy is much smaller. The main reason is that

34. When a photon falls on a metal surface of work function , the photoelectric response is

35. Photoelectrons in a retarding-potential arrangement have kinetic energies up to . A retarding potential of magnitude is applied. What is the expected result?

36. A particle’s de Broglie wavelength is . Its momentum, using , is

37. When an electron beam is accelerated through a larger potential difference before striking a crystal, the diffraction pattern changes mainly because the electrons

38. Assertion: Photoelectric emission starts nearly instantaneously when suitable radiation falls on a metal surface.
Reason: In the photon picture, a single photon can transfer its energy as a whole to one electron.

39. The de Broglie wavelength of a particle of momentum is

40. A record of four surface-emission cases is shown below.

Which case contains the mismatched named process?

41. For light of wavelength , a photoelectric experiment gives stopping potential . Using , the work function of the metal is closest to

42. In electron diffraction, clear diffraction maxima are expected when the electron de Broglie wavelength is

43. The graph description below is used.

The most suitable reason for the shift of the maximum is that changing the voltage changes

44. Electron diffraction by a crystal is strong evidence for matter waves because diffraction is normally a property of

45. Match the observation or idea with the aspect it supports.

The proper matching is

46. A statement says, “Doubling the intensity of above-threshold light doubles the stopping potential.” The most accurate correction is that doubling intensity

47. Use the situation below.

What is the strongest reason for using two different energy routes?

48. A compact graph record gives the following results for a photoelectric surface: the - line cuts the frequency axis at , and at the stopping potential is . The work function and are respectively

49. A light beam of fixed intensity is changed from frequency to frequency , and the illuminated area remains the same. The photon arrival rate becomes

50. When a photon falls on a metal of work function , Einstein’s equation implies