How does the deviation produced by a triangular prism depend on the colour (or wavelength) of light incident on it?

(a) Write the approximate wavelengths for (i) blue and (ii) red light.

(b) The wavelength of violet and red light are 4000 Å and 8000 Å respectively.

Which of the two has higher frequency?

Name the seven prominent colours of the white light spectrum in order of their increasing frequencies.

The wavelengths for the light of red and blue colours are nearly 7.8 x 10^-7 m and 4.8 x 10^-7 m respectively.

(a) Which colour has the greater speed in vacuum?

(b) Which colour has greater speed in glass?