PDF chapter test TRY NOW

Section B: Give a short answer to the question given below.
 
How could the white light of the Sun give us various colours of the rainbow?
 
Let us find it out through an activity.
 
Procedure:
  • 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, as shown in the figure.
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Dispersion of white light by the glass prism
  • Turn the prism slowly until the light that comes out of it appears on a nearby screen
What do you observe?
 
You will find a .
 
Why does this happen?
 
The prism has probably .
 
Observe the colours that appear at the two extremes of the colour band.
 
What is the sequence of colours that you observe on the screen?
Answer variants:
Indigo
Blue
Violet
Orange
Red
Green
Yellow
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