Ultrasound and infra sound

Question 0

Describe what happens to ultrasound waves as they pass from one medium to another.

Answer 0

Some of the ultrasound will reflect off o the medium and the rest of it will refract and change its speed depending on the density of the medium it is travelling to and from.

Question 1

Define ultrasound.

Answer 1

Sound above 20KHz

Question 2

Explain how to measure how far away a boundary is using ultrasound.

Answer 2

By sending ultrasound towards the boundary we can calculate the distance by multiplying how long it took for the sound to come back by the speed of which the ultrasound is traveling and then dividing the answer by 2 as the previous answer is the whole of the distance that the sound traveled and we only want the distance to the boundary is.

Question 3

Give three uses of ultrasound.

Answer 3

Communication between animals
Sonar
Foetal scanning

Question 4

What word describes a sound wave being reflected off of a boundary?

Answer 4

Echo

Question 5

Why aren’t x-rays used instead of ultrasound waves when scanning babies inside the mothers womb?

Answer 5

X-rays can cause harm to the baby (e.g. cell mutation, cell damage, cancer), whereas ultrasound doesn’t harm the mother or child.

Question 6

What animals use ultrasound and for what two purposes?

Answer 6

Bats are an example of animals that use ultrasound, they use it in order to see (hear) where they are going and to communicate with other bats.

Question 7

Define infrasound.

Answer 7

Sound under 20Hz

Question 8

Give three uses of infrasound.

Answer 8

Communication between animas
Detection of animal movements
Volcanic eruptions, meteor strikes and earthquakes.