Class 7 Science Chapter 8, Measurement of Time and Motion, follows 100-metre sprinter Prerna as she wonders how races are timed to fractions of a second. It covers ancient timekeeping devices, simple pendulums, SI units, speed calculations, and uniform vs non-uniform linear motion.
What Class 7 Science Chapter 8 Covers
8.1 Measurement of Time traces sundials, water clocks (ghati-yantra), hourglasses and quartz/atomic clocks, then experiments with a simple pendulum (oscillation and time period, 8.1.1) and defines the SI unit of time—the second (8.1.2).
8.2–8.3 Slow or Fast & Speed defines speed as distance covered per unit time (Speed = Distance / Time), compares m/s and km/h, and shows how speedometers and odometers work (8.3.1).
8.4 Uniform and Non-uniform Linear Motion distinguishes objects moving along a straight line at constant speed (uniform linear motion) from objects whose speed keeps changing (non-uniform linear motion).
Exercises in Chapter 8
- In a Nutshell key points summary and Let Us Enhance Our Learning chapter exercises.
- Exploratory Projects and Dive Deeper hands-on science activities.
Read Class 7 Science Chapter 8 Online
More Chapters
- Previous: Chapter 7: Heat Transfer in Nature
- Next: Chapter 9: Life Processes in Animals
- Hindi medium: Class 7 Science Chapter 8 PDF in Hindi (Jigyasa)
- All Science chapters and the other Class 7 books: Class 7 NCERT books 2026-27
- All Class 1 to 12 NCERT Textbooks: NCERT Books PDF (Class 1–12)
FAQ
What is the time period of a simple pendulum?
The time period is the time taken by the pendulum bob to complete one full oscillation; for a given length, it remains constant regardless of small changes in bob mass or release angle.
What is the formula for speed and its SI unit?
Speed = Total Distance Covered / Total Time Taken. Its SI unit is metre per second (m/s), while kilometre per hour (km/h) is used for larger distances.