| A | B |
|---|
| ultrasonic | scanning during pregnancy |
| infra red | used to make thermographs |
| X- Rays | used to show skeleton bones |
| Gamma rays | used to sterilise surgical instruments |
| Thermometer | used to measure temperature |
| stethoscope | for listening to heart and chest sounds |
| ultraviolet | used to kill bacteria in water supplies |
| CAT scan | makes 3 D picture of body |
| decibel | unit used for loudness of sound |
| tracer | radioactive material injected into the body |
| thermo-luminescent strip | type of colour coded thermometer |
| concave lens | used to improve short sight |
| convex lens | used to improve long sight |
| endoscope | fibre optic used to look inside the body |
| gamma camera | detects radiation from source inside the body |
| alpha particle | same as a Helium nucleus |
| beta particle | electron ejected from the nucleuswhen a neutron decays |
| Becquerel | unit of activity |
| half-life | Time taken for half of the source to decay |
| retina | light sensitive lining in the eye |
| pupil | dark entrance the inner eye |
| iris | coloured ring around the pupil |
| Formula for power of a lens | P = 1/(f in metres) |
| formula for dose equivalent | H = Q D |
| formula for absorbed dose | D = E/m |
| the point to which a lens bends light bends | focus |
| unit of loudness of sound | dBa |
| normal frequency range for a human | 20 to 20,000 Hz |
| speed of light in air | 3,000,000 metres per sec |
| needed to stop gamma rays | thick concrete or lead |
