For Class 8, 9 & 10

Foundation - a strong base in Physics, Chemistry, Maths & Biology

Concept-first questions with clear model answers across all four subjects, aligned to NCERT. Start early, build the habit, and walk into your board exams, NEET and JEE already ahead.

Showing 1 question for Class 8. Tap a card to reveal the answer.

PhysicsSoundeasy

How is sound produced, and why can it not travel through vacuum?

Reveal answer ↓

What it is

Sound is a vibration that travels by shaking the particles of a medium.

Answer

Sound is produced by vibrating objects; the vibrations push the particles of the surrounding medium, creating compressions and rarefactions that travel outward as a wave. Sound needs a material medium (solid, liquid or gas) because it moves by making particles vibrate. In a vacuum there are no particles, so sound cannot travel.

  • Produced by vibration
  • Travels as compressions and rarefactions
  • Needs a material medium
  • Cannot travel in vacuum (no particles)

Why learn this

It's why space is silent for astronauts and why you hear an approaching train through the rails first.

💡 Memory trick

No particles, no sound - a vacuum means silence.