Light and Sound.
|Magnification.|| The image height |
The object height
|Sound waves.||Sound waves cannot travel through a vaccum and they are longitudinal waves. Light waves are transverse waves.|
|Amplitude.||When a sound gets louder, the amplitude increases.|
|Pitch.||If the frequency of the sound increases(the number of waves per second) this increases the pitch.|
|Ultra Sound.||For each pulse of ultra sound that the probe sends out, it detects reflected pulses from the different boundaries in the path of the transmitted pulse. The probe is slowly moved over the body surface to build up an image of internal tissue boundaries.|
|Advantages of using Ultrasound.|| Non ionising and so harmless when used for scanning, unlike x-rays.|
Reflected at boundaries between different types of tissues so they can be used to scan organs.
Also can be used to detect flaws in metal castings.