Earth, Moon, and the Sun Part 2: MCQs (Q26–Q50)

Part 2 — Earth: Revolution, Seasons & Effects (Questions 26–50)

26. The motion of Earth around the Sun is called:

A. Rotation
B. Revolution ✅ Correct answer: B
C. Oscillation
D. Wobble
Explanations:
A) Rotation is spin on axis — incorrect.
B) Correct — revolution is orbital motion around Sun (one year).
C/D) Not standard terms for Earth’s yearly motion.

27. The time taken by Earth to complete one revolution around the Sun is about:

A. 24 hours
B. 28 days
C. 365.25 days (≈365 days 6 hours) ✅ Correct answer: C
D. 1000 days
Explanations:
A) That’s rotation — incorrect.
B) 28 days approximates lunar month — incorrect.
C) Correct — ~365¼ days; leap year adjustment every 4 years.
D) Incorrect.

28. The main reason for seasons on Earth is:

A. Change in distance from Sun during revolution
B. Tilt of Earth’s axis (approx. 23.5°) and revolution around Sun ✅ Correct answer: B
C. Moon’s phases
D. Sun’s daily rotation speed
Explanations:
A) Distance variation has minor effect; tilt dominates — incorrect.
B) Correct — tilt causes different hemispheres to receive varying sunlight angles over year.
C/D) Incorrect.

29. When Northern Hemisphere experiences summer, Southern Hemisphere experiences:

A. Summer too
B. Winter ✅ Correct answer: B
C. No seasons
D. Equinox only
Explanations:
A) Opposite seasons in hemispheres — incorrect.
B) Correct — tilt causes opposite seasons.
C/D) Incorrect.

30. The longest day in the Northern Hemisphere occurs on:

A. Vernal equinox (around 21 March)
B. Summer solstice (around 21 June) ✅ Correct answer: B
C. Winter solstice (around 21 December)
D. Autumnal equinox (around 23 September)
Explanations:
A/C/D) Equinoxes have equal day/night; winter solstice has shortest day in NH — incorrect.
B) Correct — summer solstice day longest in NH.

31. During summer in Northern Hemisphere, the Sun’s rays fall:

A. Indirectly at high latitudes only
B. More directly on Northern latitudes causing higher heating ✅ Correct answer: B
C. Equally everywhere on Earth
D. Only on the South Pole
Explanations:
A/C/D) Incorrect.
B) Correct — higher solar altitude increases energy per unit area.

32. The perihelion (Earth nearest Sun) occurs in early January. Does this cause northern summers?

A. Yes — proximity causes summer.
B. No — seasons are due to axial tilt, not small distance changes. ✅ Correct answer: B
C. Seasons are caused by Moon only.
D. Seasons are random.
Explanations:
A) Incorrect — perihelion in January occurs during NH winter.
B) Correct — tilt controls seasons; distance effect minor.
C/D) Incorrect.

33. The Tropic of Cancer is located at which approximate latitude?

A. 0°
B. 23.5°N ✅ Correct answer: B
C. 66.5°N
D. 90°N
Explanations:
A) Equator is 0° — incorrect.
B) Correct — Tropic of Cancer near 23.5°N, northernmost direct overhead Sun on summer solstice.
C/D) Incorrect.

34. When the Sun is directly overhead at Tropic of Capricorn, which season is it in Southern Hemisphere?

A. Winter
B. Summer (around 21 December) ✅ Correct answer: B
C. Equinox
D. Spring only at equator
Explanations:
A/C/D) Incorrect.
B) Correct — Sun overhead Tropic of Capricorn in southern summer (NH winter).

35. On equinox days, the Sun rises exactly in the:

A. North
B. East ✅ Correct answer: B
C. West
D. South
Explanations:
A/C/D) Incorrect.
B) Correct — on equinox, Sun rises due east and sets due west for all latitudes (neglecting refraction).

36. The tilt of Earth’s axis remains pointed towards the same star (Polaris) as it revolves. This causes:

A. No seasons anywhere
B. Seasons (because one hemisphere tilts toward Sun at different times) ✅ Correct answer: B
C. The Moon to disappear
D. The Sun to stop shining
Explanations:
A/C/D) Incorrect.
B) Correct — constant axial tilt orientation as Earth orbits causes seasonal changes.

37. If Earth had no tilt (0°), then:

A. There would be extreme seasons.
B. There would be very little or no seasonal variation. ✅ Correct answer: B
C. Day and night would stop.
D. We would have two Suns.
Explanations:
A) Opposite — tilt causes seasons — incorrect.
B) Correct — without tilt, sunlight distribution remains similar year-round.
C/D) Not true.

38. Which statement is TRUE about the Sun’s path on the sky (analemma) over a year?

A. It is constant and does not change.
B. It varies due to Earth’s tilt and elliptical orbit. Correct answer: B ✅
C. It goes below horizon at noon.
D. It causes daily tides.
Explanations:
A/C/D) Incorrect.
B) Correct — Sun’s declination and equation of time change due to tilt and orbital eccentricity.

39. The seasons on Earth are primarily a result of:

A. Variation of Sun’s brightness weekly
B. Inclination (tilt) of Earth’s axis and its revolution around Sun ✅ Correct answer: B
C. Rotation speed change daily
D. Tidal forces only
Explanations:
A/C/D) Incorrect.
B) Correct.

40. During the Northern Hemisphere winter, the North Pole is:

A. Tilted toward the Sun
B. Tilted away from the Sun ✅ Correct answer: B
C. In continuous daylight all year
D. Closer to Sun than equator always
Explanations:
A/C/D) Incorrect.
B) Correct — causing shorter days and lower Sun angle.

41. Which lines mark the limits of the tropics where Sun can be overhead at some time of year?

A. Arctic/Antarctic circles
B. Tropic of Cancer and Tropic of Capricorn ✅ Correct answer: B
C. Prime meridian only
D. Equator and poles
Explanations:
A/C/D) Incorrect.
B) Correct — Sun overhead between these latitudes during the year.

42. Seasonal changes in constellations observed at night are due to:

A. Earth’s rotation only
B. Earth’s revolution around the Sun (different night-side faces the stars) ✅ Correct answer: B
C. Moon’s phases only
D. Sun’s brightness change only
Explanations:
A) Rotation causes daily apparent motion, not seasonal changes — incorrect.
B) Correct — as Earth orbits, night side faces different parts of sky.
C/D) Incorrect.

43. The apparent movement of the Sun northwards or southwards during the year is called:

A. Precession
B. Solar declination change due to axial tilt (apparent motion along the ecliptic) ✅ Correct answer: B
C. Tectonic drift
D. Lunar libration
Explanations:
A) Precession is slow wobble over thousands of years — different phenomenon — incorrect.
B) Correct — seasonal apparent motion along ecliptic changes Sun’s declination.
C/D) Incorrect.

44. On which date does the Northern Hemisphere experience the shortest day (winter solstice)?

A. Around 21 June
B. Around 21 December ✅ Correct answer: B
C. Around 21 March
D. Around 23 September
Explanations:
A) June is summer solstice NH — incorrect.
B) Correct — December solstice: shortest day in NH.
C/D) Equinoxes have equal day/night — incorrect.

45. The reason the Sun appears higher in the sky in summer is because:

A. The Sun moves closer physically.
B. Earth’s tilt causes Sun’s apparent path (higher altitude at midday) ✅ Correct answer: B
C. The Moon pushes the Sun up.
D. Sun becomes larger physically.
Explanations:
A/C/D) Incorrect.
B) Correct.

46. The angle of incidence of Sun’s rays determines:

A. Color of the Sun only
B. Intensity of heating and effective area receiving sunlight ✅ Correct answer: B
C. Moon phases only
D. Direction of Earth’s rotation
Explanations:
A/C/D) Incorrect.
B) Correct — steep angles concentrate energy, shallow spread it.

47. If Earth’s orbital speed around the Sun changed drastically, which would be affected?

A. Length of day only
B. Length of year and season timing ✅ Correct answer: B
C. Moon’s internal composition
D. Human blood type
Explanations:
A) Day length from rotation — not revolution — incorrect.
B) Correct — orbital period defines year length.
C/D) Irrelevant.

48. Why is it warmer in summer even though the Earth may be slightly farther from the Sun?

A. More greenhouse gases only at summer.
B. Sun’s rays strike more directly and for longer periods due to tilt. ✅ Correct answer: B
C. The Moon adds heat.
D. Summer always means closer distance, without exception.
Explanations:
A/C/D) Not accurate primary reasons.
B) Correct — tilt increases solar heating despite small distance changes.

49. A solar noon at a place is when:

A. Sun rises.
B. Sun reaches highest point in sky at that location (meridian crossing). ✅ Correct answer: B
C. Sun sets.
D. Moon eclipses Sun.
Explanations:
A/C/D) Incorrect.
B) Correct.

50. The apparent path of the Sun on the celestial sphere over a year is called the:

A. Celestial equator only
B. Ecliptic ✅ Correct answer: B
C. Meridian only
D. Zodiac belt only
Explanations:
A/C/D) Not the Sun’s path name.
B) Correct — Earth’s orbital plane intersection with celestial sphere traced by Sun is ecliptic.

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