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Question
State two differences between an umbra and a penumbra.
Solution
Umbra
- It is the portion of shadow where no light reaches from the source of light due to the opaque object.
- It is completely dark.
Penumbra
- It is the portion of shadow where a portion of light from the source of light reaches the shadow even in the presence of the opaque object in between them.
- It is not completely dark but is dim (or less bright).
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