Question 1

How day and night occur on the Earth due to its rotation? (Page 172)

Accepted Answer

Day and night occur because the Earth rotates on its axis from west to east. As it rotates, the side facing the Sun experiences day, and the side away from the Sun experiences night.

Source: This question is from Earth Moon and the Sun, Science &mdash; Class 7, CBSE Board.
Key Concepts CoveredThis question tests your understanding of the following concepts from the chapter Earth Moon and the Sun: Day, Night, Occur, Earth, Due, Rotation. These are fundamental topics in Science that students are expected to master as part of the CBSE Class 7 curriculum.A thorough understanding of these concepts will help you answer similar questions confidently in your CBSE examinations. These topics are frequently tested in both objective and subjective sections of Science papers. We recommend revising the relevant section of your textbook alongside practising these solved examples to build a strong foundation.
How to Approach This QuestionRead the question carefully and identify what is being asked. Break down complex questions into smaller parts. Use the terminology and concepts discussed in this chapter. Structure your answer logically — begin with a definition or key statement, then provide supporting details. Review your answer to ensure it addresses all parts of the question completely.
Key Points to RememberRead the question carefully and identify all parts before answering.
Use the terminology specific to this subject and chapter.
Review the textbook content for this chapter before attempting questions.
Practice writing concise, well-structured answers within time limits.
Related Questions from Earth Moon and the SunQ10: The Indian cricket team matches in Australia are often held in December. Should they pack winter or...
Q11: Why do you think lunar eclipses can be seen from a large part of the Earth when they happen, but...
Q12: If the Earth’s axis were not tilted with respect to the axis of revolution, explain what would be...
Q13: Four friends used the following ways to see the solar eclipse. Who among them was being careless?...
Q15: The Moon is much smaller than the Sun, yet it can block the Sun completely from our view during a...
Practice more questions from Earth Moon and the Sun &mdash; Science, Class 7 CBSE

Question 2

Since the Earth is rotating, shouldn’t the stars also appears to move in the sky like the Sun? (Page 1 74)

Accepted Answer

Yes, since the Earth rotates from west to east, the stars appear to move across the sky from east to west, just like the Sun. This movement is only apparent it happens because the Earth is spinning on its axis.

Question 3

Why do different stars appear in the night sky over the course of a year? (Page 175)

Accepted Answer

We see different stars at night during the year because the Earth moves around the Sun. As it moves, the part of the sky we can see at night also changes, so new stars and constellations become visible in different months.

Question 4

We go through a cycle of seasons every year. Is it related to the revolution of the Earth around the Sun in some way? (Page 1 77)

Accepted Answer

Yes, the cycle of seasons is related to the Earth’s revolution around the Sun. As the Earth revolves around the Sun, its tilted axis causes different parts of the Earth to receive different amounts of sunlight at different times of the year. This change in sunlight causes the seasons.

Question 5

Why days are longer in summer than in winter? (Page 177)

Accepted Answer

Days are longer in summer than in winter because the Earth’s axis is tilted. During summer, your part of the Earth is tilted towards the Sun, so it gets more sunlight for a longer time each day.

Question 6

Could the light from the Sun get blocked by the two planets which are revolving between the Earth and the Sun? (Page 1 79)

Accepted Answer

No, the light from the Sun does not usually get blocked by the two planets (Mercury and Venus) because they are very small compared to the Sun and are far away from the Earth. Sometimes they do come between the Earth and the Sun, but they block only a small part of the sunlight and it’s hardly noticeable from Earth.
NCERT Class 7 Science Chapter 12 Question Answer Earth Moon and the Sun (Exercise)
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Question 7

Four friends used the following ways to see the solar eclipse. Who among them was being careless?
(i) Ravikiran used a solar eclipse goggle.
(ii) Jyothi used a mirror to project the Sun’s image.
(iii) Adithya saw the Sun directly with his eyes.
(iv) Aruna attended a programme arranged by a planetarium.

Accepted Answer

(iii) Adithya was being careless because he looked at the Sun directly with his eyes, which can damage eyesight. The safe ways to view a solar eclipse are using solar eclipse glasses, indirect viewing methods, or attending guided programmes.

Question 8

Fill in the blanks
(i) Stars rise in the ______ and set in the _______.

Accepted Answer

east, west(ii) Day and night are caused by the Earth’s _______Answer:rotation(iii) When the Moon fully covers the Sun from our view, it is called a _______ solar eclipse.Answer:total

Question 9

The Moon is much smaller than the Sun, yet it can block the Sun completely from our view during a total solar eclipse. Why is it possible?

Accepted Answer

The Moon and the Sun look almost the same size from Earth, even though the Moon is much smaller. This happens because the Moon is much closer to Earth than the Sun. Since the Moon appears nearly the same size as the Sun in the sky, it can completely cover the Sun during a total solar eclipse.

Question 10

The Indian cricket team matches in Australia are often held in December. Should they pack winter or summer clothes for their trip?

Accepted Answer

They should pack summer clothes for their trip. In Australia, December falls in summer because it is in the Southern Hemisphere, where the seasons are opposite to those in India. So while it’s winter in India in December, it is summer in Australia.

Question 11

Why do you think lunar eclipses can be seen from a large part of the Earth when they happen, but total solar eclipse can be seen by only a small part of the Earth?

Accepted Answer

A lunar eclipse can be seen from a large part of the Earth because the Earth’s shadow is big, and it covers the Moon for a longer time. Everyone on the night side of the Earth can see it. But a total solar eclipse is visible only for a few minutes and from a small area, because the Moon’s shadow is small and moves quickly across the Earth due to the Moon’s motion and Earth’s rotation.

Question 12

If the Earth’s axis were not tilted with respect to the axis of revolution, explain what would be the effect on seasons?

Accepted Answer

If the Earth’s axis were not tilted, there would be no seasons. Every place on Earth would get the same amount of sunlight throughout the year. As a result, the weather would stay almost the same all year round  no summer, winter, spring, or autumn. The length of days and nights would also stay nearly equal every day.
Class 7 Earth Moon and the Sun Question Answer (Activities)
Activity 12.1: Let us Explore (Page 170)
Fig. A girl observing objects around her while riding a merry-go-round
Observation and conclusion:
• When we are on a rotating object, like a merry- go-round, the surroundings seem to move in the opposite direction.
• When we fix our gaze at a particular tree, the tree appears to move around us in the opposite direction, that is, clockwise direction.
• In the same way, as the Earth rotates from west to east, the Sun appears to move from east to west. Therefore, it is actually the Earth’s rotation that makes the Sun appear to move.
Activity 12.2: Let Us Explore (Pages 171-172)
Fig. (a): Using a globe to understand rotation of the Earth, (b): Using a globe and a torchlight to understand day and night
Observation and conclusion: This activity helps us understand how the Earth’s rotation from west to east causes day and night. As the globe turns, different parts move into light (day) and then into darkness (night). The Sun appears to rise in the east, move across the sky, and set in the west. This shows that the movement of the Sun in the sky is due to the Earth’s rotation.
Activity 12.3: Let Us Explore (Page 174)
Fig. Illustrative sketch of Big Dipper (for activity 12.3) by a student located in Pune on the night of 1-2 April
Observation and conclusion: This activity shows that the stars appear to move in the night sky because of the Earth’s rotation from west to east. The Pole Star looks almost fixed as it lies close to the Earth’s axis, while the Big Dipper appears to move around it. This apparent movement helps us understand how the sky changes over time due to Earth’s rotation.
Activity 12.4: Let Us Explore (Page 180)
Fig. Trying to cover a friend’s head with the thumb
Observation and conclusion: This activity shows that the apparent size of an object depends on both its actual size and how far it is from the observer. Even though the Sun is much bigger than the Moon, they look similar in size from Earth because the Moon is much closer to us. That’s why the Moon can also appear to cover the entire Sun during a solar eclipse.

Question 13

Four friends used the following ways to see the solar eclipse. Who among them was being careless?
(i) Ravikiran used a solar eclipse goggle.
(ii) Jyothi used a mirror to project the Sun’s image.
(iii) Adithya saw the Sun directly with his eyes.
(iv) Aruna attended a programme arranged by a planetarium.

Accepted Answer

(iii) Adithya was being careless because he looked at the Sun directly with his eyes, which can damage eyesight. The safe ways to view a solar eclipse are using solar eclipse glasses, indirect viewing methods, or attending guided programmes.

Question 14

The Moon is much smaller than the Sun, yet it can block the Sun completely from our view during a total solar eclipse. Why is it possible?

Accepted Answer

The Moon and the Sun look almost the same size from Earth, even though the Moon is much smaller. This happens because the Moon is much closer to Earth than the Sun. Since the Moon appears nearly the same size as the Sun in the sky, it can completely cover the Sun during a total solar eclipse.

Question 15

The Indian cricket team matches in Australia are often held in December. Should they pack winter or summer clothes for their trip?

Accepted Answer

They should pack summer clothes for their trip. In Australia, December falls in summer because it is in the Southern Hemisphere, where the seasons are opposite to those in India. So while it’s winter in India in December, it is summer in Australia.

Question 16

Why do you think lunar eclipses can be seen from a large part of the Earth when they happen, but total solar eclipse can be seen by only a small part of the Earth?

Accepted Answer

A lunar eclipse can be seen from a large part of the Earth because the Earth’s shadow is big, and it covers the Moon for a longer time. Everyone on the night side of the Earth can see it. But a total solar eclipse is visible only for a few minutes and from a small area, because the Moon’s shadow is small and moves quickly across the Earth due to the Moon’s motion and Earth’s rotation.

Question 17

If the Earth’s axis were not tilted with respect to the axis of revolution, explain what would be the effect on seasons?

Accepted Answer

If the Earth’s axis were not tilted, there would be no seasons. Every place on Earth would get the same amount of sunlight throughout the year. As a result, the weather would stay almost the same all year round  no summer, winter, spring, or autumn. The length of days and nights would also stay nearly equal every day.Class 7 Earth Moon and the Sun Question Answer (Activities)Activity 12.1: Let us Explore (Page 170)Fig. A girl observing objects around her while riding a merry-go-roundObservation and conclusion:• When we are on a rotating object, like a merry- go-round, the surroundings seem to move in the opposite direction.• When we fix our gaze at a particular tree, the tree appears to move around us in the opposite direction, that is, clockwise direction.• In the same way, as the Earth rotates from west to east, the Sun appears to move from east to west. Therefore, it is actually the Earth’s rotation that makes the Sun appear to move.Activity 12.2: Let Us Explore (Pages 171-172)Fig. (a): Using a globe to understand rotation of the Earth, (b): Using a globe and a torchlight to understand day and nightObservation and conclusion: This activity helps us understand how the Earth’s rotation from west to east causes day and night. As the globe turns, different parts move into light (day) and then into darkness (night). The Sun appears to rise in the east, move across the sky, and set in the west. This shows that the movement of the Sun in the sky is due to the Earth’s rotation.Activity 12.3: Let Us Explore (Page 174)Fig. Illustrative sketch of Big Dipper (for activity 12.3) by a student located in Pune on the night of 1-2 AprilObservation and conclusion: This activity shows that the stars appear to move in the night sky because of the Earth’s rotation from west to east. The Pole Star looks almost fixed as it lies close to the Earth’s axis, while the Big Dipper appears to move around it. This apparent movement helps us understand how the sky changes over time due to Earth’s rotation.Activity 12.4: Let Us Explore (Page 180)Fig. Trying to cover a friend’s head with the thumbObservation and conclusion: This activity shows that the apparent size of an object depends on both its actual size and how far it is from the observer. Even though the Sun is much bigger than the Moon, they look similar in size from Earth because the Moon is much closer to us. That’s why the Moon can also appear to cover the entire Sun during a solar eclipse.