Q # 1
A ray of light in air strikes a glass surface. Is there a range of angles for which total internal reflection occurs? Explain.
Answer
Q # 2
Interference can occur in thin film. Why is it important that the films be thin? Why don’t you get these effects with a relatively thick film? Where should you put the dividing line between “thin” and “thick”? Explain your reasoning
Answer
A simple plastic food wrap does not act as a polarizer, hence it do not affect the polarized light, but when it is stretched in any particular direction, it’s molecules or arranged such that it becomes a polarizer, axis of which is along the direction in which it is stretched. Hence when placed between two crossed polarizer some amount of light is passed through them.
Q # 3
Light traveling in air is incident on the surface of a block of plastic at an angle of 72.7° to
the normal and is bent so that it makes a 57.1° angle with the normal in the plastic. Find
the speed of light in the plastic.
Answer
Q # 4
Yes, water waves can be reflected and retracted for example, when a water wave traveling in a pond, strikes it’s surface, it is reflected back another example of reflection can be seen at sea-shores .
Refraction of water waves can be seen in the oceans where two streams of different temperature meet due to difference in temperature, density of water is changed and hence refractive index changes, due to this difference in density, water waves are refracted from one medium to another, Huygens’s principle is also applied to water waves and is valid for all transverse waves and water waves .Water waves are also transverse waves, hence Huygens’s principles is valid for water waves.
