Question

In dispersion without deviation

• A. The emergent rays of all the colours are parallel to the incident ray.
• B. Yellow coloured ray is parallel to the incident ray.
• C. Only red coloured ray is parallel to the incident ray.
• D. All these rays are parallel, but not parallel to the incident ray.

Answer 1

The correct option is B Yellow coloured ray is parallel to the incident ray.

Deviation is zero only for a particular colour, it is generally taken to be yellow.