WEAKNESSES - Waves

uses of radiowaves

broadcasting and communications

uses of microwaves

cooking and satellite transmissions

uses of infrared waves

heaters and night vision equipment

uses of visible light waves

optical fibres and photography

uses of ultraviolet waves

fluorescent lamps

uses of x-rays

observing the internal structure of objects and materials, including for medical applications

uses of gamma waves

sterilising food and medical equipment

conditions for total internal reflection

• angle greater than critical angle

• going into a faster medium

what is the critical angle?

• into a faster medium

• light refracts along the boundary

• angle of refraction is 90

describe how an oscilloscope can be used to measure the time period of a sound wave. (4)

• connect microphone

• adjust the time base for a stable trace

• count number of squares for one complete cycle

• time period = number of squares x time base scale