Phenomena and Applications of Reflection of Sound Waves

An echo

Sound waves are reflected from a hard surface to the listener

Places that have an echo

Enclosed halls, empty rooms, caves and tunnels

Ultrasound

Type of sound wave with a frequency of more than 20 000 Hz

Characteristic of ultrasound

Cannot be heard by humans but can be heard by animals such as bats

Sonar

A sound reflection technology that is used in shipping industry to detect underwater objects

Limitation of hearing the frequency of sound by human

20 Hz to 20 000 Hz

Example of animals that have higher range of hearing than humans

Bats, dolphins and dogs

Devices to overcome human limitations of hearing

Stethoscopes, megaphone and hearing aids

Hearing range (Hz) for bats

2000 - 110 000 Hz

Ways for stethoscopes that help to overcome human limitation of hearing

Help doctors listen to a patient's heartbeat