Physics · KS3 Y7 · Waves (Light & Sound)

Light & sound basics

Light & sound basicsFree2:37Heddy Score 3 of 7, below the standard

What you need to know

  • Light is a transverse wave, and like other waves it has an amplitude, a wavelength and a frequency.
  • For visible light, different frequencies are seen as different colours.
  • Radio waves, microwaves, infrared, visible, ultraviolet, X-rays and gamma rays form one electromagnetic spectrum, differing only in wavelength.
  • All electromagnetic waves travel at about 300 million metres per second in a vacuum, and wave speed = frequency × wavelength.

In this clip

Runs 2:37, from 0:09 to 2:46 of the full video.

Heddy Score3/7, Below the standard
See the seven stars
  • Trusted source · passed. The creator's own upload, live and playable here.
  • On the map · not judged yet. A teacher watched it: it mainly teaches this map topic.
  • Spec-true · not judged yet. Accurate, and right for the current UK specification.
  • Focused · passed. One idea, short enough to watch in one go.
  • Accessible · passed. Good captions, clear sound and pictures.
  • Safe for children · not judged yet. Right for 11 to 16 year olds, with no sales pitch.
  • Proven · not judged yet. Earned from our students: they learn from it, find it helpful and watch it to the end.
★ passed · ☆ pending · ✕ failed
Our students

Not enough students yet

Our own students' answers. These are what move ★7 Proven.
On YouTube

1.53M views · 20K likes · Professor Dave Explains 4.49M subscribers

As reported by YouTube on 2026-11-01. Not part of the Heddy Score.
How the Heddy Score works

Why we picked it

A short, accurate overview of light as a wave and its place in the electromagnetic spectrum.

Professor Dave Explains on YouTubechecked 2026-10-22

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