Page 162 - Volt Elevate The World Around Us Book 4

Flex Your Brain

A. Fill in the blanks.

1. In some hilly areas, underground water comes out to the surface as
________________.
2. ________________ is a small body of water surrounded by land.

3. ________________ are artificial lakes built behind dams to collect water.

4. ________________ are built across rivers to block or control the flow of water.

5. Sweat dries up due to ________________.

B. Write True or False. Also rectify the incorrect statements.
1. Half of the earth’s surface is covered with water. ____________

2. Rainwater that seeps into the soil is called ground water. ____________

3. Snow-fed rivers are also called perennial rivers. ____________

4. Water is circulated continuously in nature in the form of
the water cycle. ____________

C. Match the following columns.
Column A Column B

1. Weight (a) Remains the same everywhere

2. Mass (b) Explains why some objects float or sink

3. Density (c) Upward push of water on objects

4. Ship (d) Less dense overall because of hollow
structure
5. Buoyant Force (e) Force of Earth’s pull due to gravity

D. Answer the following questions.

1. What is the difference between weight and mass?

2. Why does a stone feel heavier than a wooden block of the same size?

3. How does density explain floating and sinking of objects?
4. Why does an iron ship float in water even though iron is dense?

5. Give two examples each of objects that float and sink in water.

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