21 (c) Different types of medical scans use ultrasound. Look at the diagram of an ultrasound wave travelling in air. M high pressure
normal air pressure
distance along wave
low pressure L wave diagram Compare the separation of the air particles in areas L and M and explain how the diagram shows that this is a longitudinal wave. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... .............................................................................................................................................. [2] [Total: 10]
Š OCR 2013
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