Chapter Exam

Chapter 10: Sound Waves: Characteristics and Applications — Online MCQ Test

Q: Which of the following is the correct definition of sound?

Answer: A. A form of energy produced by vibrating bodies — Sound is produced when an object vibrates and the energy is transferred through a medium. It is not related to light, magnetism, or chemical reactions.

Q: Sound waves in air are which type of waves?

Answer: B. Longitudinal waves — In air, sound travels as longitudinal waves because the particles vibrate parallel to the direction of propagation.

Q: Why can sound not travel in vacuum?

Answer: A. Because sound needs a medium for propagation — Sound requires a material medium such as air, water, or solids to travel. It cannot propagate in vacuum.

Q: Two sound waves travel in the same medium. Wave A has larger amplitude than Wave B, but both have the same frequency. Which statement is correct?

Answer: B. Wave A has higher loudness and same pitch — Amplitude determines loudness, while frequency determines pitch. If frequency is the same, the pitch remains the same.

SCIENCE · Grade 9 · CBSE(NCERT)

Practice Chapter 10: Sound Waves: Characteristics and Applications with a free chapter-wise online MCQ test for CBSE(NCERT) Grade 9 SCIENCE. This chapter covers: Sound Wave Longitudinal Wave Frequency Wavelength Amplitude Echo SONAR Pitch Loudness Vibration Propagation Understanding sound production wave properties transmission echoes and p.... AI-generated questions from basic to board-exam level, with instant results and explanations.

Questions

20m

Time Limit

Attempts Left

10 random questions from this chapter (mixed difficulty)
Questions you've seen before won't repeat until the pool resets
You have 20 minutes — exam auto-submits when time is up
Maximum 3 attempts per chapter
Results and explanations shown immediately after submission

New here? Register free — includes 3 free chapter exams.

Chapter 10: Sound Waves: Characteristics and Applications — Important Questions & Answers (FAQ)

Frequently asked questions from CBSE(NCERT) Grade 9 SCIENCE — Chapter 10: Sound Waves: Characteristics and Applications, with answers and explanations. These are sample questions; the exam has its own separate question set.

Which of the following is the correct definition of sound?

A. A form of energy produced by vibrating bodies ✓
B. A form of light produced by hot objects
C. A magnetic force acting between objects
D. A chemical reaction in air

Answer: A. A form of energy produced by vibrating bodies
Sound is produced when an object vibrates and the energy is transferred through a medium. It is not related to light, magnetism, or chemical reactions.

Sound waves in air are which type of waves?

A. Transverse waves
B. Longitudinal waves ✓
C. Electromagnetic waves
D. Surface waves

Answer: B. Longitudinal waves
In air, sound travels as longitudinal waves because the particles vibrate parallel to the direction of propagation.

Why can sound not travel in vacuum?

A. Because sound needs a medium for propagation ✓
B. Because vacuum blocks vibrations completely
C. Because sound is made of light rays
D. Because air is the only medium for sound

Answer: A. Because sound needs a medium for propagation
Sound requires a material medium such as air, water, or solids to travel. It cannot propagate in vacuum.

Two sound waves travel in the same medium. Wave A has larger amplitude than Wave B, but both have the same frequency. Which statement is correct?

A. Wave A has higher pitch and lower loudness
B. Wave A has higher loudness and same pitch ✓
C. Wave A has lower loudness and higher pitch
D. Wave A has different speed and different wavelength necessarily

Answer: B. Wave A has higher loudness and same pitch
Amplitude determines loudness, while frequency determines pitch. If frequency is the same, the pitch remains the same.

A person hears a sound of 25 Hz. Which statement is most appropriate according to CBSE NCERT?

A. It is an infrasonic sound, below the audible range of humans ✓
B. It is ultrasonic and heard clearly by humans
C. It is a very loud sound
D. It is an echo

Answer: A. It is an infrasonic sound, below the audible range of humans
Human beings can generally hear sounds from about 20 Hz to 20,000 Hz. A 25 Hz sound lies below the lower limit and is infrasonic.