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Question
Answer the following.
How is a shadow formed? Write the conditions required for a shadow to form.
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Solution
Whenlightfallsonanopaqueobject, light is obstructed and a dark patch on a screen kept behind is called the shadow. This is because light propagates in a straight line.
If the distance between the object and screen is less, the shadow will be (umbra) dark and smaller.
If the distance is increased shadow will be dim and larger.
Conditions Required for a shadow to form are:
- There should be a source of light.
- An opaque object.
- A screen.
- The opaque object is placed between the source of light and the screen.
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