Page 137 - Viva ICSE Science 4 : E-book

9. The smaller the object the greater is the friction.

10. Friction causes wear and tear of machine parts.

C. Answer the following in one word.

1. Fuel used in vehicles to reduce the release of harmful gases _______________

2. The gas that is important for burning _______________

3. Name a gas which can dissolve in water. _______________

4. When two liquids dissolve completely, they are called _______________

5. Man-made light sources are called _______________

6. A living organism that has the ability to produce light _______________

7. Measuring device commonly used by tailors _______________

8. The fi rst person to discover gravitational force _______________

9. Material that is used to reduce friction between moving
parts of a machine _______________

10. The force that pulls down every object towards the
centre of the earth _______________

D. Match the following.

Column A Column B

1. Fish (a) a substance that dissolves
2. Immiscible liquids (b) breathe through spiracles

3. Candle (c) breathe through gills

4. Insects (d) put rollers

5. Kilogram (e) does not allow light to pass
through it

6. Solute (f) liquids that do not mix together

7. Opaque object (g) standard unit of measuring length

8. Metre (h) luminous object

9. Kicking football (i) standard unit of measuring mass

10. Unable to pull heavy suitcase (j) muscular force

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