5. Motion of the Earth (ICSE 4th Class) SST Notes

5. Motion of the Earth

 Read and answer

Define :

1) Northern Hemisphere - - the part of the Earth that is to the north of the equator.

2) Southern Hemisphere - the part of the Earth that is to the south of the equator

3) Equator - the imaginary line drawn midway between the north pole and the south pole

A. Match the columns.

1. Nicolaus Copernicus  - a path along which the Earth revolves

2. west to east                 - b. spring, summer, autumn and winter the Earth moves around the Sun

3. Orbit                           - c. the Earth moves around the Sun

4. Seasons                      - d. shorter days than nights

5. Winter                        - e. direction of the Earth's rotation

(Answers: 1 – c , 2 – e , 3 – a , 4 – b , 5 – d )

B. Fill in the blanks with words from the brackets.

1. The Earth rotates on its ………… (axis/orbit). (Ans : axis)

2. The part of the Earth which has ……… (day/night) is turned away from the Sun. (Ans : night)

3. A leap year has ………… (365/366) days. (Ans : 366)

4. The ………….. (rotation/revolution) of the Earth causes seasons. (revolution)

5. When it is summer in the Northern Hemisphere, it is ………….. (winter/summer) in the Southern Hemisphere. (Ans : winter)

C. Answer these questions.

1. What is axis of the Earth?

Ans : The axis of the Earth is an imaginary tilted line that passes thought the center of the Earth and connects the poles

2. What is rotation? What does it cause?

Ans : The Earth's motion on its axis is called rotation. Rotation causes day and right.

3. What is revolution? How long does the Earth take to complete one revolution?

Ans : The motion of the Earth around the sun is called revolution. The Earth takes 365 days to complete one revolution

4. What happens in the Southern Hemisphere when the South Pole is tilted towards the Sun?

Ans : When the south pole is tilted towards the sun the southern hemisphere gets more sunlight Hence, it has summer.

5. What happens when the Sun's rays are on the Equator?

Ans : When the Sun's rays are on the Equator, the Length of the days and night are the same throughout the world. Thus, it is neither very hot nor very cold in both the hemispheres....

E. Picture study

Look at the picture of Nicolaus Copernicus. Answer the questions.

1. What did he say?
 Ans : Nicolaus Copernicus said that the earth only appears to the stationary. In fact the Earth spins on its own axis and also moves around the sun.

2. Name the two motions of the Earth.
Ans : The two motion of the Earth are rotation and revolution

G. SITUATIONAL THINKING

Read these sentences. Colour the boxes blue for rotation and red for revolution.

1. We experience summer, winter, spring and autumn.  (Ans : Red )
2. One year has 365 days.  (Ans : Red )             
3. The Earth spins on its axis. (Ans : Blue )
4. Days and nights occur on Earth. (Ans : Blue )
5. The Earth moves along its orbit. (Ans : Red )
6. The Sun rises in the east and sets in the west.  (Ans : Blue )


J. You have read that sunlight causes day. The Sun is a natural source of light. Meanings of some words related to light are given. Write the words. Choose from the box.

(rainbow, shadow,  reflection, photosynthesis, transparent)

1. The process of preparing food by green plants using sunlight - ……………….

(Ans – photosynthesis )

2. Throwing back of light by a non-luminous object without absorbing it ……………….

(Ans - reflection)

3. This is seen in the sky after rain due to the splitting of white light by water droplets………………. (Ans - rainbow)

4. These objects allow light to pass through them……………….

(Ans - transparent)

5. The dark patch formed behind an object when the object blocks the path of light……………….

(Ans - shadow)