Sound — Class 8 Science NCERT Solutions (Free)

Free step-by-step NCERT solutions for Class 8 Science chapter "Sound" — 8 important questions with detailed answers for CBSE board exam preparation.

TL;DR: Free step-by-step NCERT solutions for Class 8 Science chapter "Sound" — 8 important questions with detailed answers for CBSE board exam preparation.

By Syllab.in · Updated Jun 14, 2026

Key Questions Covered:

Define sound. How is it produced?
A tuning fork vibrates 256 times per second. Find its frequency and time period.
What is the relationship between frequency and pitch? Explain with example.
Can sound travel in vacuum? Why or why not?
Define amplitude and loudness. How are they related?
A sound wave has a frequency of 50 Hz and travels at 340 m/s. Find its wavele…
+ 2 more questions in the full chapter

Solutions Summary:

Question	Status
Define sound. How is it produced?	✓ Solved
A tuning fork vibrates 256 times per second. Find its fre…	✓ Solved
What is the relationship between frequency and pitch? Exp…	✓ Solved
Can sound travel in vacuum? Why or why not?	✓ Solved
Define amplitude and loudness. How are they related?	✓ Solved
A sound wave has a frequency of 50 Hz and travels at 340 …	✓ Solved

Showing 6 of 8 questions

Q1: Define sound. How is it produced?

Sound is a form of energy that produces a sensation of hearing. It is produced by vibrating objects. Vibrations create disturbances in the medium (air, water, solid), forming sound waves that travel and reach our ears, causing the eardrum to vibrate, transmitting signals to the brain.

Q2: A tuning fork vibrates 256 times per second. Find its frequency and time period.

Step 1: Frequency f = 256 Hz (given: 256 vibrations/second) Step 2: Time period T = 1/f = 1/256 = 0.0039 seconds Frequency = 256 Hz, Time period ≈ 0.004 s or 3.9 milliseconds

Q3: What is the relationship between frequency and pitch? Explain with example.

Pitch is directly related to frequency. Higher frequency → higher pitch (shriller sound). Lower frequency → lower pitch (deeper sound). Example: A small whistle produces high-frequency sound (high pitch), while a drum produces low-frequency sound (low pitch). Human ear perceives frequency as pitch.

Q4: Can sound travel in vacuum? Why or why not?

No, sound cannot travel in vacuum. Sound requires a medium (air, water, or solid) to propagate. Sound waves are longitudinal waves that need particles to vibrate and transfer energy. In vacuum, there are no particles, so sound waves cannot form or travel. This is why space is silent.

Q5: Define amplitude and loudness. How are they related?

Amplitude is the maximum displacement of a vibrating object from its mean position. Loudness is the perception of sound intensity by the human ear. Loudness is directly proportional to amplitude: greater amplitude → louder sound. Loudness is measured in decibels (dB).

Q6: A sound wave has a frequency of 50 Hz and travels at 340 m/s. Find its wavelength.

Step 1: Use v = f × λ (where v = speed, f = frequency, λ = wavelength) Step 2: 340 = 50 × λ Step 3: λ = 340/50 = 6.8 m Wavelength = 6.8 meters

Showing 6 of 8 questions. Visit the full page for complete solutions.