Get Answers to all your Questions

header-bg qa

Activity on dispersion of light

Answers (1)

  • Take a thick sheet of cardboard and make a small hole or narrow slit in its middle.
  • Allow sunlight to fall on the narrow slit. This gives a narrow beam of white light. 
  • Now, take a glass prism and allow the light from the slit to fall on one of its faces.
  • Turn the prism slowly until the light that comes out of it appears on a nearby screen . W
  • What do you observe? You will find a beautiful band of colours. Why does this happen?

The prism has split the incident white light into a band of colours. The various colours seen are Violet, Indigo, Blue, Green, Yellow, Orange and Red (VIBGYOR). The band of the coloured components of a light beam is called its spectrum.

Different colours of light bend through different angles with respect to the incident ray, as they pass through a prism. The red light bends the least while the violet the most. Thus the rays of each colour emerge along different paths and thus become distinct.

Posted by

shubham.krishnan

View full answer