Which of the following is correct when a ray of light passes from a rarer medium to a denser medium:

(1) speed will decrease
(2) frequency remains unchanged
(3) wavelength will decrease
(4) intensity will decrease

1. (1)
2. (1) and (4)
3. (1), (2) and (4)
4. all of the above

The refractive index of water is 4/3 and that of glass is 3/2. The refractive index of glass with respect to water is:

1. 9/8
2. 2
3. 8/9
4. 1

The highest refractive index is of:

1. glass
2. water
3. diamond
4. Ruby