Class 9 Science — Chapter 3: Motion
90 practice questions · 30 Easy · 30 Medium · 30 Hard
Practise Class 9 Science Chapter 3, "Motion", with 90 NCERT-aligned multiple-choice questions. The set is split into 30 Easy, 30 Medium and 30 Hard questions, so you can warm up on the fundamentals and then push into the exam-level problems that separate top scorers in CBSE Board exams and the JEE & NEET foundation years.
"Motion" 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 (+2 correct, −1 wrong, 0 skipped), training the same 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 Motion, 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 9 Science mastery score. A few sample questions are shown below; sign in free to practise all 90.
Key concepts: Motion (Class 9 Science)
This chapter covers the laws of chemical combination, atomic and molecular masses, the mole concept, and how chemical formulae are written.
- Laws of chemical combination
- Law of conservation of mass (mass is neither created nor destroyed) and law of constant proportions (a compound always has the same ratio of elements by mass).
- Atomic & molecular mass
- Atomic mass is the mass of an atom relative to 1/12 of a carbon-12 atom (in u); molecular mass is the sum of the atomic masses in a molecule.
- Mole concept
- One mole is 6.022 × 10²³ particles (Avogadro's number) and equals the gram atomic/molecular mass of a substance.
- Valency and ions
- Valency is the combining capacity of an element; ions are charged atoms or groups (cations +, anions −) used to write formulae.
- Chemical formulae
- Written by balancing the valencies (criss-cross method); the formula gives the ratio of atoms in a compound.
Key formulas — Motion
💡 Exam tips for Motion
- Molar mass in grams contains exactly one mole (6.022 × 10²³) of particles — the bridge between mass and number.
- Use the criss-cross method on valencies to write a correct chemical formula quickly.
Sample questions
Which of the following is a vector quantity?
Displacement has both magnitude and direction, making it a vector quantity. Distance, speed, and time are scalar quantities.
A car starts from rest and reaches a velocity of 20 m/s in 10 s. What is its acceleration?
a = (v − u) / t = (20 − 0) / 10 = 2 m/s². Starting from rest means u = 0.
A v-t graph shows: velocity increases from 0 to 30 m/s in 10 s, stays at 30 m/s for 5 s, then decreases to 0 in 15 s. Total displacement is:
Displacement = area under the v–t graph = ½(10)(30) + (30)(5) + ½(15)(30) = 150 + 150 + 225 = 525 m.
Motion — FAQs
What are the key concepts in Class 9 Science Motion?+
This chapter covers the laws of chemical combination, atomic and molecular masses, the mole concept, and how chemical formulae are written. Key ideas include Laws of chemical combination, Atomic & molecular mass, Mole concept, Valency and ions, Chemical formulae.
What does Class 9 Science Chapter 3 (Motion) cover on XamBaaz?+
It covers 90 NCERT-aligned MCQs on "Motion" — 30 Easy, 30 Medium and 30 Hard — each with a timed quiz and an instant explanation, suitable for CBSE Board exams and the JEE & NEET foundation years.
Are these "Motion" questions free to practise?+
Yes — sign in with Google to practise "Motion" free. Full unlimited access is ₹999/year (limited-time launch price), with no per-chapter charges.
How should I revise "Motion" 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.
Practise all 90 questions free
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