When a ray of white light falls on a prism, which of the following statements are correct ?

1. The dispersion of white light occurs at the first surface of the prism.
2. The deviation of light rays occurs at both the surfaces of the prism.
3. The prism does not produce colours, but it only splits the various colours present in the white light.
4. All of the above.

The correct arrangement of colours in an increasing order of their wavelengths is :

1. Violet < Green < Red
2. Red < Green < Violet
3. Green < Violet < Red
4. Green < Red < Violet

A beam consisting of red, blue and yellow colours is incident normally on the face AB of an isosceles right-angled prism ABC as shown in the figure given below. Critical angle of glass-air interface for yellow colour is 45°.

Out of the four emergent rays P, Q, R and S, which one is for the yellow colour :

1. P
2. Q
3. R
4. S

The frequency of violet light is 7.5 x 10¹⁴ Hz. Its wavelength in nm is :

1. 7500 nm
2. 4000 nm
3. 400 nm
4. 750 nm