Viva help for Optics Experiments

1. Define refractive index.
   
2. WHat is the least value of refractive index possible?
   
3. What can you infer if someone says that he has a medium of refractive index less than one?
   
4. Define focus.
   
5. Define pole of a spherical mirror.
   
6. Define optic centre.
   
7. What is spherical abberration?
   
8. WHat is chromatic abberration?
   
9. What is the focal length of a plane mirror?
   
10. How will you distinguish between a plane mirror, concave mirror and a convex mirror without feeling its surface with your hand?
    
11. Under what conditions can a plane mirror for a real image?
    
12. What are the differences between convex lens and concave lens?
    
13. What is dispersion?
    
14. Why a glass slab does not produce dispersion whereas a prism does?
    
15. Define refractive angle of the prism.
    
16. What is parallax?
    
17. What is index correction?
    
18. How is parallax removed?
    
19. What are the practical uses of a concave mirror?
    
20. Why a concave mirror is considered better as a makeup mirror?
    
21. Why the reflectors used in search lights are paraboloidal and not concave?
    
22. Distinguish real image and virtual image.
    
23. Why mirrors are silvered on the back surface?
    
24. Why a convesx mirror is preferred as the rear view mirror of vehicles?
    
25. What is the principle on which the working of a simple microscope is based?
    
26. Define power of a lens.
    
27. Define angle of deviation
    
28. What are the factors on which the lateral displacement produced by a glass slab depend?
    
29. Define critical angle for a pair of media
    
30. What is total internal reflection?
    
31. What are the applications of total interna reflection?
    
32. What is angle of minimum deviation?
    
33. What are the factors on which the deviation produced by a prism depends
    
34. What is the cause of dispersion?
    
35. Why atravelling microscope is called so?
    
36.