Science Waves, Light & Sound Conceptual 11–12 yrs

How Sound Waves Travel

声波的传播方式

Description

Explain that sound is produced by vibrating objects and travels as a longitudinal pressure wave through solids, liquids, and gases; describe reflection of sound (echoes) and absorption; explain why sound cannot travel through a vacuum

Mastery Evidence

✓ Explains how a vibrating object creates regions of compression and rarefaction in air
✓ Explains why sound travels fastest in solids and cannot travel in a vacuum
✓ Describes how an echo is produced and gives a practical application (sonar, ultrasound)
✓ Explains what sound absorption means and why soft furnishings reduce echoes

Assessment Prompt

If your child heard an echo in a large empty hall, could they explain what causes the echo, why the same sound in a carpeted living room doesn’t echo, and what would happen to sound in outer space?