Class 8 Science — Chapter 11: Keeping Time with the Skies
72 practice questions · 24 Easy · 24 Medium · 24 Hard
Practise the most important Class 8 Science questions from Chapter 11, "Keeping Time with the Skies" — 72 NCERT-aligned multiple-choice questions with answers and explanations. The set is split into 24 Easy, 24 Medium and 24 Hard, so you can warm up on the fundamentals and then push into the exam-level problems that separate top scorers in CBSE Board exams.
"Keeping Time with the Skies" is one of the chapters where concept clarity across physics, chemistry and biology basics really pays off. Each MCQ on this chapter is timed and uses exam-grade marking (+4 correct, −1 wrong, 0 skipped), training the same negative-marking accuracy-under-pressure that real papers demand. Every question carries a short explanation, so a wrong answer becomes a quick lesson rather than a dead end — the fastest way to close gaps before a test.
Use this chapter as targeted revision: attempt the Easy set first to confirm your basics on Keeping Time with the Skies, then move to Medium and Hard to test application and problem-solving. Your accuracy, streaks and XP save automatically, and the chapter feeds into your overall Class 8 Science mastery score. A sample question is shown below; sign in free to see its answer and practise all 72.
Key concepts: Keeping Time with the Skies (Class 8 Science)
This chapter shows how people learned to keep time by watching the sky. The Moon shines by reflecting sunlight, and as it orbits the Earth we see its phases — from the invisible new Moon, through the growing waxing period (Shukla Paksha), to the full Moon, and back through the waning period (Krishna Paksha) — a cycle of about 29.5 days, a lunar month. From these cycles came lunar calendars, while the Earth's roughly 365-day revolution around the Sun gave the solar (Gregorian) calendar with its leap years. The Earth's rotation makes day and night, its revolution makes the year and seasons, and the alignment of the Sun, Earth and Moon causes eclipses.
- The Moon reflects sunlight
- The Moon makes no light of its own; we see the half of it that is lit by the Sun.
- Phases of the Moon
- The changing shapes of the bright Moon: the invisible new Moon, the full bright disc of the full Moon, and the shapes in between.
- Waxing and waning
- In the waxing period (Shukla Paksha) the lit part grows towards full Moon; in the waning period (Krishna Paksha) it shrinks towards new Moon.
- Cause of the phases
- The phase we see depends on the relative positions of the Sun, Moon and Earth as the Moon orbits, so different amounts of its lit half face us.
Try a sample question
One free sample from this chapter — sign in to check your answer and practise the rest.
The phase of the Moon depends on the relative positions of the:
Unlock the full chapter — free
See the answer and solution to this question, then practise all 72 questions (24 Easy · 24 Medium · 24 Hard) with timed scoring and instant feedback, plus the complete key-concept notes, formulas & exam tips. Sign in with Google — no card needed.
Start this chapter free →Keeping Time with the Skies — FAQs
What are the key concepts in Class 8 Science Keeping Time with the Skies?+
This chapter shows how people learned to keep time by watching the sky. The Moon shines by reflecting sunlight, and as it orbits the Earth we see its phases — from the invisible new Moon, through the growing waxing period (Shukla Paksha), to the full Moon, and back through the waning period (Krishna Paksha) — a cycle of about 29.5 days, a lunar month. From these cycles came lunar calendars, while the Earth's roughly 365-day revolution around the Sun gave the solar (Gregorian) calendar with its leap years. The Earth's rotation makes day and night, its revolution makes the year and seasons, and the alignment of the Sun, Earth and Moon causes eclipses. Key ideas include The Moon reflects sunlight, Phases of the Moon, Waxing and waning, Cause of the phases.
What does Class 8 Science Chapter 11 (Keeping Time with the Skies) cover on XamBaaz?+
It covers 72 NCERT-aligned MCQs on "Keeping Time with the Skies" — 24 Easy, 24 Medium and 24 Hard — each with a timed quiz and an instant explanation, suitable for CBSE Board exams.
Are these "Keeping Time with the Skies" questions free to practise?+
Yes — sign in with Google to practise "Keeping Time with the Skies" free. Full unlimited access is ₹999/year (limited-time launch price), with no per-chapter charges.
How should I revise "Keeping Time with the Skies" for the exam?+
Start with the Easy quiz to confirm your fundamentals, then attempt Medium and Hard for application-level practice. Review each explanation, retry the questions you miss, and track your accuracy on this chapter until it is consistently high.
Are these "Keeping Time with the Skies" MCQs available with answers?+
Yes. This page shows one sample question so you can see the format; sign in free with Google to reveal the correct option and a step-by-step "Why" explanation for it, then practise all 72 questions with instant scoring.
Is there negative marking in the "Keeping Time with the Skies" quizzes?+
Yes — the timed quizzes use exam-grade marking: +4 for a correct answer, −1 for a wrong one and 0 for a skipped question, so you practise the same negative-marking discipline as CBSE Board exams.
Are these important questions for Keeping Time with the Skies?+
The set is curated to the NCERT syllabus and weighted toward the question patterns that actually appear in CBSE Board exams, across Easy, Medium and Hard — so it doubles as an "important questions" revision list for "Keeping Time with the Skies".