Class Clips is changing
We will be introducing the new Knowledge and Learning Beta website over the coming months. Clips for use in the classroom are now available on your phone, tablet or PC.


Alternatively, you can still browse or search by keyword or clip number on this site.

CLIP 10866

Silence!

Silence!
Play

Did you know?

All Class Clips content is available to watch on mobile, tablet and desktop devices on our new Knowledge & Learning BETA website.

Key Info
  • Silence!
  • Duration: 01:49
  • Sound travels by molecules in the air knocking into one another. Bang goes the Theory presenter, Jem, silences an angle grinder by removing the air – recreating conditions in space in a vacuum in a bell jar. An angle grinder is suspended inside a vacuum in a bell jar, mirroring the classic demonstration of an alarm clock in a bell jar. When the grinder is turned on, no noise can be heard. As air is allowed into the jar, noise can be heard. In addition, sparks can be seen as carbon dust ignites in the atmospheric oxygen.
  • Subject:

    Science

       Topic:

    Phys: Waves - Sound and Light

  • Keywords: waves, atmosphere, vibration, noise, silence, pressure, experiment, BangGoesTheTheory. OuterSpace
Ideas for use in class
  • Pupils view the clip and produce a labelled diagram of the experiment to explain the scientific principles involved. Clip 14 from the Bang Goes the Theory teachers pack. To download the pdf please go to bbc.co.uk/schools/teachers/bang/
Background details
  • Clip language : English
  • Aspect ratio : 16x9

BBC navigation

BBC © 2014 The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.