Polarization of Light MCQ Quiz - Multiple Choice Questions & Answers Page 4

31. Optic axis is

1. an imaginary line inside the crystal
2. a real line inside the crystal
3. a real direction inside the crystal
4. none of these

32. Plane of vibration is defined only for

1. plane polarised
2. unpolarised
3. both plane polarised & unpolarised
4. neither plane polarised & nor unpolarised

33. Principle planes in calcite crystals are

1. squares
2. rhombus
3. triangles
4. parallelograms

34. Ruby laser produces the laser beam of wavelength

1. 6943 Amstrong
2. 6328 Amstrong
3. 6320 Amstrong
4. 6940 Amstrong

35. The acute angle between the planes of crystal is

1. 78 degree
2. 71 degree
3. 102 degree
4. 109 degree

36. The coherence length of Laser light is

1. 4000 Amstrong
2. 8000 Amstrong
3. 300 m
4. 2 µm

37. The He - Ne laser is

1. Continuous Laser
2. gas Laser
3. semiconductor laser
4. pulsed laser

38. The material in which the population inversion is achieve is called as

1. Active medium
2. metastable state
3. passive medium
4. stable states

39. The method of achieving population inversion in He – Ne Laser is

1. Optical pumping
2. inelastic Scattering
3. forward biasing
4. chemical reaction

40. The method of achieving population inversion in Ruby Laser is

1. Optical pumping
2. inelastic Scattering
3. forward biasing
4. chemical reaction