What is a virtual image? Give one situation where a virtual image is formed.
Virtual Image: Virtual image cannot be obtain on screen. A virtual image can be seen only by looking into a mirror. The image of our body formed by a plane mirror cannot be received on a screen, it can be seen only looking into the mirror. The virtual image is just an illusion. So, virtual images are also called unreal images. A virtual image is formed when light rays coming from an object appear to meet after reflection from the mirror. It is possible to obtain a virtual image on the screen because light rays actually do not pass through it. A plane mirror always forms virtual images. Highly polished metal objects also forms virtual images.
We cannot find any image on the white screen which is placed behind the mirror, when an object is placed very close to the concave mirror. A virtual image is formed when reflected rays appear to meet.
Such images cannot be obtained on screen.
Plane mirrors, convex mirror and concave lens always forms an virtual image.
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Classify the changes involved in the following processes as physical or chemical changes:
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Given below is a crossword puzzle based on this lesson. Use hints to fill in the blank spaces with letters that complete the words.
Down Across
(D) 1 : Thorough washing (A) 1 : Keeps warm
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Here is a crossword puzzle: Good luck!
Across
3. Liquid waste products
4. Solid waste extracted in sewage treatment
6. A word related to hygiene
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1. Used water
2. A pipe carrying sewage
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Across
2. Plantation prevents it.
5. Use should be banned to avoid soil pollution.
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3. Clay and loam are suitable for cereals like.
4. This type of soil can hold very little water.
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Match the items in Column I with those in Column II:
Column I Column II
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Given below is a crossword puzzle based on this lesson. Use hints to fill in the blank spaces with letters that complete the words.
Down Across
(D) 1 : Thorough washing (A) 1 : Keeps warm
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Across
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5. Use should be banned to avoid soil pollution.
6. Type of soil used for making pottery.
7. Living organism in the soil.Down
1. In desert soil erosion occurs through.
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4. This type of soil can hold very little water.
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Here is a crossword puzzle: Good luck!
Across
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