Interference and Diffraction Multiple Choice Questions and Answers

41. In interference experiment, by keeping all other parameters constant, if you see the thin film interference from different angles, you will observe

1. Uniform illumination of screen
2. Uniform darkness on the screen
3. Equally spaced dark and white bands
4. Few colored bands and then general illumination

42. In interference experiment, monochromatic light is replaced by white light, we will see

1. Uniform illumination of screen
2. Uniform darkness on the screen
3. Equally spaced dark and white bands
4. Few colored bands and then general illumination

43. In Michelson interferometer semi silvered mirror is used to obtain

1. Thin film interference
2. Phase coherence
3. mono chromatic light
4. colored fringe

44. In Michelson s interferometer 100 fringes cross the field view when the movable mirror is displaced through 0.0248 mm. Calculate the wavelength of monochromatic light used

1. 5896 A^o
2. 5890 A^o
3. 4000 A^o
4. 4890 A^o

45. In Newtons ring experiment, the diameter of the 15 th ring was found to be 0.590 and that of the 5th ring was 0.336 cm. If the radius of Plano convex lens is 100 cm, compute the wavelength of light used

1. 5885 A^o
2. 5880 A^o
3. 5890 A^o
4. 5850 A^o

46. In Newtons Ring experiments, the diameter of bright rings is proportional to

1. Square root of Odd Natural numbers
2. Natural Number
3. Even Natural Number
4. Square root of natural number

47. In Newtons Ring experiments, the diameter of dark rings is proportional to

1. Odd Natural numbers
2. Natural Number
3. Even Natural Number
4. Square root of natural number

48. In Newtons rings experiment, if monochromatic source of light is replaced by another monochromatic source of higher wavelength. What will be the effect on radius (or diameter)?

1. Radius (or diameter) will decrease
2. Radius (or diameter) will increase
3. There will be no effect
4. Radius (or diameter) will remain constant but there will be more brightness

49. In Newtons rings experiment, if we reduce the radius of curvature of Plano convex lens to zero, what will be effect on Newtons rings?

1. They will become brighter
2. They will become darker
3. They will disappear
4. They will be more dense

50. In Newtons rings experiment, if we reduce the radius of curvature of PlanoConvex lens to zero, what will be effect on Newtons rings?

1. They will become more bright
2. They will become more dark
3. They will disappear
4. They will be more dense