CBSE Class 7 Science Chapter 12 Earth, Moon, And The Sun MCQs Set 01

Answer: (B) The angle at which sunlight strikes Earth changes due to Earth's rotation, making the Sun appear to move across the sky

Explanation:
Though we perceive the Sun moving from East to West, this apparent motion is actually caused by Earth rotating from West to East. As the angle of the Sun's rays changes relative to vertical objects, shadow length changes accordingly.

Answer: (B) How large an object appears to our eye, which depends on both its actual size and distance from us

Explanation:
Apparent size is determined by two factors—the object's true physical dimensions and how far away it is from the observer. Two objects of different actual sizes can have similar apparent sizes if the smaller one is much closer.

Answer: (C) 22 December

Explanation:
The chapter identifies 22 December as the winter solstice in the Northern Hemisphere, when the shortest day and longest night occur.

Answer: (B) The Earth's axis of rotation points almost directly toward the Pole Star in the Northern Hemisphere

Explanation:
Because Earth's rotational axis points almost toward the Pole Star, this star appears to stay fixed in place while all other stars appear to revolve around it due to Earth's rotation.

Answer: (B) It was impressively close to the modern measurement

Explanation:
Aryabhata's value calculated around the fifth century CE was remarkably accurate and closely matches what modern scientists have determined about Earth's rotation period.

Answer: (B) The Earth rotates from West to East, so eastern locations rotate into the sunlit region first

Explanation:
Earth's rotation is from West to East, meaning locations toward the east experience the Sun's light first as they rotate into the illuminated side of Earth.

Answer: (C) Star trails

Explanation:
The chapter's fascinating facts section describes how long exposure photographs record the apparent motion of stars as circular arcs known as star trails, which result from Earth's rotation.

Answer: (B) Dark red

Explanation:
The chapter states that during a total lunar eclipse, the bright disc of the Moon appears dark red in color while it remains in Earth's shadow.

Answer: (B) Only a few minutes due to Earth's rotation and the Moon's orbital motion

Explanation:
The chapter explains that during a total solar eclipse, the Moon's shadow moves across Earth's surface due to both Earth's rotation and the Moon's motion in its orbit, making totality visible for only a few minutes from any given location.

Answer: (A) 21 March and 23 September; day and night both last approximately 12 hours

Explanation:
• Spring equinox occurs around 21 March
• Autumn equinox occurs around 23 September
• On both dates, daytime lasts approximately 12 hours
• Nighttime also lasts approximately 12 hours

Answer: (B) The tilt of Earth's axis causes the Northern Hemisphere to tilt away from the Sun in January

Explanation:
The chapter emphasizes that seasons are caused by the tilt of Earth's axis and the resulting differences in sunlight angle and duration, not by changes in distance to the Sun. In January, the Northern Hemisphere tilts away from the Sun despite being closest to it.

Answer: (A) The appearance of certain star patterns in the night sky

Explanation:
The chapter mentions that these indigenous communities used the appearance of certain patterns of stars in the sky as markers for the arrival of monsoon rain.

Answer: (B) The axis tilt causes the Northern Hemisphere to face the Sun more directly and rotate more of that hemisphere through the lit side of Earth

Explanation:
Due to the tilt of Earth's axis, in June the Northern Hemisphere is tilted toward the Sun. As a result, a larger portion of the hemisphere remains in daylight during one complete rotation, creating day lengths exceeding 12 hours.

Answer: (C) The observer's location on Earth is rotating, making stationary stars appear to move relative to the observer

Explanation:
The stars appear to move because the observer is actually rotating with Earth. Since the observer on the rotating Earth is moving relative to the fixed stars, the stars appear to shift position in the sky.

Answer: (B) A Transit of Venus

Explanation:
The chapter's "Dive Deeper" section explains that when Venus passes between the Earth and the Sun, it appears as a tiny black dot against the Sun's bright face, and this rare event is known as a Transit of Venus.

Answer: (D) Inventing the first telescope used in India

Explanation:
The chapter states that M.K. Vainu Bappu led efforts in setting up telescopes, studied stars, discovered a comet, and traveled to observe eclipses, but it does not claim he invented the first telescope used in India.

Answer: (B) Rhythmic verses called shlokas in Sanskrit

Explanation:
The fascinating facts section mentions that the Surya Siddhanta presents calculations to predict eclipses in the classical Sanskrit poetry tradition in rhythmic shlokas.

Answer: (B) The Earth's shadow on the Moon is larger than the Moon's shadow on Earth

Explanation:
The Earth is much larger than the Moon, so Earth's shadow on the Moon is correspondingly larger. This means the shadow can cover the Moon as viewed from a wide region on Earth's surface. Conversely, the Moon's much smaller shadow during a solar eclipse covers only a small area on Earth.

Answer: (B) It represents the Earth's rotation on its axis from West to East

Explanation:
Activity 12.2 explicitly states that when viewed from above the North Pole, the Earth rotates in the anti-clockwise direction, which means from West to East. The activity uses the globe's counterclockwise rotation to mirror the Earth's actual axial rotation, helping students visualize how our planet spins on its own axis in about 24 hours.

Answer: (B) Mercury and Venus are much farther from Earth than the Moon is, making their apparent size much smaller despite their larger physical size

Explanation:
Although Mercury and Venus are physically much larger than the Moon, they are vastly farther from Earth. The concept of apparent size—what we actually see from our vantage point—depends on both physical size and distance. Because the Moon is relatively close to Earth while those planets are distant, the Moon's apparent size is similar to the Sun's, allowing total blockage during eclipses. Mercury and Venus, despite being larger, appear as tiny dots and cannot block the Sun.

Answer: (B) You would see a gradual change in which stars appear at sunset throughout the year, while the North Pole observer sees mostly the same stars with only the Big Dipper moving

Explanation:
The chapter explains that Earth's revolution around the Sun causes the night sky to gradually change throughout the year as we look in different directions from our changing orbital position. At the equator, you observe this changing view over the year. However, someone at the North Pole has their location's axis pointing toward the Pole Star, which remains nearly fixed in the sky. While the Pole Star stays in place, other constellations like the Big Dipper appear to move around it, whereas at the equator the entire visible set of constellations shifts seasonally.

Answer: (B) There would be no meaningful seasonal variation in day length or sunlight intensity anywhere on Earth except the poles

Explanation:
The tilt of the Earth's axis, combined with the spherical shape of Earth, gives rise to seasons. If the axis were upright (perpendicular to the orbital plane), the sunlight would distribute equally across both hemispheres year-round, and every location would receive approximately 12 hours of daylight daily. Without the axial tilt, there would be no variation in the intensity or duration of sunlight at different latitudes, eliminating the seasonal cycle that depends on which hemisphere tilts toward or away from the Sun at different times of year.

Answer: (B) Ancient Indian astronomers made careful observations and developed sophisticated mathematical methods capable of detecting the Earth's rotation through celestial phenomena

Explanation:
Aryabhata's work, alongside the boat analogy he used—where a man in a moving boat sees stationary objects as moving backward—demonstrates that ancient Indian astronomers understood the concept of apparent motion due to the observer's movement. Aryabhata's calculated value of approximately 23 hours 56 minutes 4.1 seconds being impressively close to the currently accepted value indicates he and his contemporaries developed sophisticated observational and mathematical techniques to measure celestial cycles with precision, deriving the Earth's rotational period from the observed apparent motion of stars.