Waves and the Earth Flashcards
1
Q
What is the frequency of ultrasound
A
more than 20000Hz
2
Q
Fill in the gap:
Ultrasound get ______ reflected at a boundary between media
A
partially
3
Q
Give two uses of ultrasound
A
- Feotus scanning
2. Sonar
4
Q
What is the frequency for infrasound
A
Less than 20Hz
5
Q
Why can infrasound travel long distances?
A
Because it has a long wavelength
6
Q
What is the Earth’s surface made up of?
A
Tectonic plates
7
Q
Fill in the gap:
Earthquakes and explosions cause _______ waves
A
Seismic
8
Q
What can P-waves travel through?
A
Solids and lquids
9
Q
What can S-waves travel through?
A
Only solids
10
Q
Which is faster P or S waves
A
P waves
