Acoustics
What is acoustics?
The scientific study of sound.
What is echolocation?
The process of locating objects by emitting sounds and interpreting the reflected sound waves.
What does sonar stand for?
Sound Navigation and Ranging.
What is ultrasound?
Sound with frequencies above the range of human hearing, typically above 20,000 Hz.
What are longitudinal waves?
Waves in which the particle displacement is parallel to the direction of wave propagation.
How do soft materials affect sound?
Soft materials tend to absorb sound rather than reflect it.
Which animals use echolocation?
Bats and dolphins.
How does sonar work?
Sonar sends sound waves toward an object; the waves reflect back, and the time taken helps determine the distance.
How is ultrasound used in medicine?
For imaging organs and monitoring fetuses by reflecting sound waves off body structures.
What is the speed of sound in water?
Approximately 1,500 m/s.
What is reverberation?
The persistence of sound in a space due to multiple reflections.
How do bats use echolocation?
Bats emit sounds that bounce off objects, allowing them to determine the location and size of prey.
What is the purpose of sonar in fishing?
To locate schools of fish underwater.
What is a sonogram?
An image produced by ultrasound waves reflecting off tissues.
How does sound travel?
Sound travels through mediums like air, water, or solids as waves.
Name a material that can reduce reverberation.
Curtains, carpets, or cushioned seats.
What is one way moths can evade bats?
By emitting their own sounds to jam the bats’ echolocation.
Describe how sonar detects objects.
By emitting a sound pulse and measuring the time for the pulse to travel to the object and return.
What are some advantages of ultrasound over X-rays?
It is safer and does not use ionizing radiation.
How do sound waves behave in different mediums?
Sound travels faster in solids than in liquids, and faster in liquids than in gases
Why is reverberation a problem in music?
It can distort the sound and make it difficult to hear.
Compare echolocation to sonar.
Both use echoes to locate objects, but echolocation is natural (used by animals) while sonar is a technological system
How is sonar used in the Navy?
To locate submarines and underwater objects.
Describe how ultrasound breaks kidney stones.
Ultrasonic waves are directed at the stones, breaking them into smaller pieces that can be passed through urine.
How does temperature affect the speed of sound?
The speed of sound increases with an increase in temperature.