We can define a wave as something that carries energy from one place to another without the transfer of physical matter. To understand this definition it is useful to think about two different ways of feeling heat. In a shower, heat is created by an energy exchange inside the storage tank or shower unit and … Continue reading Key Facts: Waves
Balloon on the Moon
Imagine that you could take a helium-filled balloon to the moon. If you stood on the lunar surface, holding the ribbon tied to the bottom of the balloon, what would you expect to happen when it was released? We'll assume that the balloon doesn't burst and I'll give you four possible outcomes; The balloon rises … Continue reading Balloon on the Moon
Thawing a frozen balloon
The pressure, volume and temperature of a gas are all linked so it makes sense to keep one of them constant when investigating the interdependence of the other two. But we didn't do that when we watched the effect of liquid nitrogen on a partially-inflated balloon - as shown in the animation below. Before viewing … Continue reading Thawing a frozen balloon
Sound: A Quick Recap
Sound is the most common example of a longitudinal wave (if you need a second example in an examination, mention seismic P waves from earthquakes). It is therefore important that you can describe and explain sound waves. This includes how the human ear works (in physics terms) and how microphones and loudspeakers link sound to … Continue reading Sound: A Quick Recap
Mr Tarrant's physbang 'blog 