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Question
What do you observe when a beam of light is allowed to enter in a closed dark room through a small hole.
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Solution
We will observe randomly moving dust particles in the beam of light. This confirms the presence of dust particles in the air.
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RELATED QUESTIONS
Match the following :
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| (b) Acid rain | 2. Manganese dioxide |
| (c) Rust | 3. Carbon dioxide |
| (d) Catalyst | 4. Methane |
| (e) Photosynthesis | 5. Nitrogen Dioxide |
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- Antoine Lavoisier
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| 3. An acid formed by the dissolution of sulphur dioxide gas in water. | (c) Sulphur acid |
| 4. An acid formed by the dissolution of carbon dioxide in water. | (d) Helium |
| 5. A gas vital for respiration. | (e) Nitrogen |
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Do sailors need the help of wind to sail?
In the boxes of Column, I the letters of some words got jumbled. Arrange them in proper form in the boxes given in Column II
| Column I | Column II | ||
| (a) | \[\boxed{\text{D}}\]\[\boxed{\text{I}}\]\[\boxed{\text{L}}\]\[\boxed{\text{L}}\]\[\boxed{\text{M}}\]\[\boxed{\text{W}}\]\[\boxed{\text{I}}\]\[\boxed{\text{N}}\] | (a) | `squaresquaresquaresquaresquaresquaresquare square` |
| (b) | \[\boxed{\text{Y}}\]\[\boxed{\text{N}}\]\[\boxed{\text{O}}\]\[\boxed{\text{G}}\]\[\boxed{\text{X}}\]\[\boxed{\text{E}}\] | (b) | `squaresquaresquaresquaresquare square` |
| (c) | \[\boxed{\text{M}}\]\[\boxed{\text{E}}\]\[\boxed{\text{S}}\]\[\boxed{\text{K}}\]\[\boxed{\text{O}}\] | (c) | `squaresquaresquaresquaresquare` |
| (d) | \[\boxed{\text{T}}\]\[\boxed{\text{U}}\]\[\boxed{\text{D}}\]\[\boxed{\text{S}}\] | (d) | `squaresquaresquare` |
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Air is a ______ of some gases.
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