P1.5 - AQA GCSE Physics Unit 1 - Overview

P1.5	The use of waves for communication and to provide evidence that the universe is expanding Electromagnetic radiations travel as waves and move energy from one place to another. They can all travel through a vacuum and do so at the same speed. The waves cover a continuous range of wavelengths called the electromagnetic spectrum. Sound waves and some mechanical waves are longitudinal, and cannot travel through a vacuum. Current evidence suggests that the universe is expanding and that matter and space expanded violently and rapidly from a very small initial 'point', ie the universe began with a 'big bang'. Candidates should use their skills, knowledge and understanding to:
	■ compare the use of different types of waves for communication	Knowledge and understanding of waves used for communication is limited to: sound, light, microwaves, radiowaves, infrared waves,
	■ evaluate the possible risks involving the use of mobile phones	There is a section in 'News' that includes mobile phone related news reports. This will give you an idea of how controversial this issue is.
	■ consider the limitations of the model that scientists use to explain how the universe began and why the universe continues to expand.

There are four sections to this part of the syllabus:

P1.5.1 - General properties of waves

P1.5.2 - Reflection

P1.5.3 - Sound

P1.5.4 - Red-shift

There is also a page suggesting practical experiments that should be carried out during the study of this section.