Advertisements
Advertisements
Question
The critical angle for glass-air is 45° for the light of yellow colour. State whether it will be less than, equal to, or more than 45° for (i) ref light, (ii) blue light?
Advertisements
Solution
As the wavelength decreases (or increases) refractive index becomes more (or less) and critical angle becomes less (or more).
(i) For red light the critical angle will be more than 45° and
(ii) For blue light the critical angle will be less than 45°.
RELATED QUESTIONS
Draw the diagram given below and clearly show the path taken by the emergent ray.
Light passes through a rectangular glass slab and through a triangular glass prism. In what way does the direction of the two emergent beams differ and why?
Light of a single colour is passed through a liquid having a piece of glass suspended in it. On changing the temperature of liquid, at a particular temperature the glass piece is not seen. When is the glass piece not seen?
When a lighted candle is held in front of a thick plane glass mirror, several images can be seen, but the second image is the brightest, give reason.
A light ray in passing from water to a medium
(a) speeds up
(b) slows down. In each case, give one example of the medium.
In fig 4.18, name the ray which represents the correct path of light while emerging out through a glass block.
Name the colour of white light which is deviated the most on passing through a prism.
A fish swimming in a pond seems nearer than it really is. Explain.
Complete the ray diagram showing its emergence into the air after passing through the prism.
The velocity of light in diamond is 121000 kms-1. What is its refractive index?
