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प्रश्न
State two differences between an umbra and a penumbra.
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उत्तर
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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संबंधित प्रश्न
Fill in the blank.
The less dark portion of a shadow is called the .................
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What are the essential conditions for the formation of shadow?
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The shape of the shadow obtained in two positions is shown in the following figure.
Match the position of the torch and shape of the shadow of the ball.
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