Ultrasonic waves are waves that have a frequency greater than 20 kHz so cannot be heard by humans
When an ultrasonic wave meets a boundary between two different media , it is partiallyreflected
How can ultrasonic waves be used to determine how far away a boundary is?
By measuring the time taken for reflected ultrasonic waves to return to a detector
Ultrasonic waves can be used in industry -They can be used to detect defects in materials without cutting into them - Defects could be manufacturing faults (cracks and air bubbles) or damage (corrosion)
State how ultrasonic waves are used in medicine?
They are used for pre natal scanning , detection of kidneystones and tumours , and producing images of damaged ligaments and muscles
Ultrasound scanners can produce images of internal organs (such as a kidney or the heart) - This works for any organ that is not surrounded by bone - Ultrasound can also be used to produce images of a foetus
Why is Ultrasound safer than X-rays?
It does not cause mutations and does not increase the risk of cancer
