Sound is everywhere — but do you know exactly how it’s produced and why it can’t travel through empty space? This quiz covers NCERT book Exploration’s Class 9 Science, Chapter 10, Sections 10.1 and 10.2: the vibration-based production of sound, and why a material medium (solid, liquid, or gas) is essential for it to propagate.
You’ll be tested on the tuning fork activity, the vacuum bell jar experiment, and real-world applications like why astronauts can’t hear each other in space. The quiz includes straightforward concept-check questions as well as assertion-reasoning and case-study style questions in the pattern used in recent CBSE exams. Each question comes with a detailed explanation, so it doubles as a quick revision tool.
Haven’t covered the theory yet? Read the full notes first: Production and Propagation of Sound – Class 9 Notes, then come back and test yourself here.
What this quiz covers
- How vibrations produce sound (and why vibration stopping stops the sound)
- How the human voice box (larynx) and vocal cords produce sound
- Why sound needs a material medium — solid, liquid, or gas
- The tuning-fork-in-water activity (Activity 10.2) and what it proves
- The scratching-desk activity (Activity 10.3) showing sound travel through solids
- The vacuum bell jar experiment (Section 10.2.1) and why sound fades as air is pumped out
- Real-life application: why astronauts can’t hear each other directly in space
- Assertion-reasoning and case-based question formats (CBSE exam pattern)
Production and Propagation of Sound MCQ
🧠 Production and Propagation of Sound Quiz
General Instructions
- Your test contains multiple-choice questions with only one answer type questions. There are a total of 20 questions
- This is a 20 min test. Please make sure you complete it in stipulated time
- You can finish this test any time using the 'Submit' button.
Frequently asked questions
Q: What produces sound in an object?
A: Sound is produced when an object vibrates — that is, moves rapidly to and fro. The vibration disturbs the particles of the surrounding medium, and this disturbance travels outward as sound. Once the object stops vibrating, the sound stops too.
Q: Why can’t sound travel through a vacuum?
A: Sound is a mechanical wave, which means it needs particles of a medium (solid, liquid, or gas) to travel by making them vibrate and pass the disturbance along. A vacuum has no particles, so there’s nothing to carry the vibration, and sound cannot propagate through it.
Q: Can sound travel through solids and liquids, not just air?
A: Yes. Sound travels through solids, liquids, and gases — in fact it usually travels fastest through solids and slowest through gases. This is why sound is audible through a wall or through water, and why placing an ear against a table lets you hear a faint scratch on its surface.
Q: Why can’t astronauts hear each other directly in space?
A: Outer space is close to a vacuum, with virtually no air or other matter to carry sound waves. Since astronauts have no medium to transmit vibrations between them, they rely on radio communication built into their spacesuits instead of speaking directly.
Q: What does the vacuum bell jar experiment show about sound?
A: In this experiment, a ringing electric bell is placed inside a sealed jar, and air is gradually pumped out. As the air is removed, the sound grows fainter and eventually becomes almost inaudible, demonstrating that sound needs air (or another medium) to travel.
