Physics · KS3 Y7 · Forces & Motion

Friction and drag

Friction and dragFree4:30Heddy Score 3 of 7, below the standard
Next clip

What you need to know

  • Friction is a force from a surface that acts against an object sliding along it.
  • Rough surfaces give more friction than smooth ones, and even smooth-looking surfaces are bumpy at a microscopic level.
  • It is harder to start an object moving than to keep it moving, because the friction before it slides can be larger.
  • Friction is useful for walking and for car tyre grip; air resistance is a kind of friction from a fluid.

In this clip

Runs 4:30, from 0:26 to 4:56 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

956K views · 16.5K likes · Professor Dave Explains 4.49M subscribers

As reported by YouTube on 2026-11-02. Not part of the Heddy Score.
How the Heddy Score works

Why we picked it

Explains clearly where friction comes from and why it can be both a nuisance and essential, ending with air resistance.

Professor Dave Explains on YouTubechecked 2026-10-22

Plays from youtube-nocookie.com. No YouTube cookies until you press play.