Physics XI Karachi Board True and False - Chapter 9

Chapter 9 - Wave Aspect of Light
1. Maxwell presented wave theory of light.

2. No phenomenon can be explained from both particle and wave nature of light.

3. Newton suggested corpuscular theory for light.

4. Changing magnetic field can produce electric field.

5. Stationary magnetic field can produce electric field.

6. The speed of light in free space is 3 x 108 m/s.

7. Maxwell presented electromagnetic theory.

8. The wavelength of visible light is less than 4000A°.

9. The wavelength of X-rays is of order of 1 nm.

10. Millikan was awarded Noble Prize in 1923.

11. Photoelectric effect and Compton effect can be explained by corpuscular theory.

12. The distance between two consecutive wave fronts is equal to one half of wavelength.

13. When two monochromatic waves of light reach at a point in phase, they are said to interfere destructively.

14. Interference of light is a result of superposition of two waves.

15. Light waves are electromagnetic waves.

16. X-rays are mechanical waves.

17. Light waves are longitudinal in nature.

18. Light can not be polarized.

19. Newton’s rings are formed due to diffraction of light.

20. In thin film interference, the condition for constructive and destructive interference is same as that for ordinary interference.

21. To obtain Newton’s rings a convex lex of very large radius of curvature is required.

22. Diffraction is a special type of interference.

23. Diffraction is observed due to obstructed parts of a wave front.

24. Newton’s rings can be obtained by using ordinary light.

25. In Newton’s rings the central ring is always bright.


26. Two independent monochromatic sources can produce interference pattern in Young’s Experiment.

27. Semi silvered plate is used in Michelson’s interferometer to obtain phase coherence.

28. Newton’s rings are formed due to the phenomenon of thin film interference.

29. The formation of interference fringes in Michelson’s Interferometer can be explained on the basis of thin film interference.

30. In Michelson’s Interferometer a broad or exteded source of monochromatic light is required.

31. Diffraction grating can also be termed as interference grating.

32. X-rays can be diffracted by using a diffraction grating.

33. The grating element is equal to the length of diffraction grating.

34. A diffraction grating is a glass plate on which few lines are ruled per cm.

35. In Michelson’s Interferometer both complete mirrors should be moveable.

36. In Fraunhofer’ diffraction both screen and source are removed at a large distance from the diffracting object.

37. In Fresnel diffraction only screen is at finite distance where as source is at infinite distance from diffracting object.

38. Interference fringes can be obtained in Young’s Experiment by using ordinary light.

39. Longitudinal waves can be detected by using the phenomenon of polarization.

40. Intensity of light increases while passing through tourmaline crystal.

41. When light passes through tourmaline crystal magnetic vector is absorbed completely.

42. Polarization can be used to determine the concentration of sugar in solution.

43. The relation ml = d sin q is called Bragg’s Law.

44. In diffraction pattern the bright hands are of non-uniform intensity.

45. For constructive interference, in thin film interference, the path difference should be zero or integral multiple of wavelength.