Ultrasonic waves are those waves which have frequency more than 20 kHz.
Bats use ultrasonic waves to fly and search for their prey at night without colliding.
Bat produces ultrasound waves in the direction of its way and hear back the echoes produced by reflection of the waves while striking the object in the path. Through this process they judge the position of the object and change their path.
Role of ultrasound waves in Medical science:
Imaging of internal body structure and functioning of heart in humans.
Breaking of stones produced in kidney into smaller ones to flush out through urination.
Observing the foetus development in the mother’s womb for any abnormality or defect