1.
Option B
2.
Option C
3.
Option B
4.
Option B
5.
The speed of sound is 770 miles per hour in air.
6.
An oscilloscope is an electronic measuring instrument used to display constantly varying
signals.
7.
Greater frequency causes higher pitch.
8.
Option A
9.
Alternating current comes from a wall socket.
10.
Option C
11.
Option B
12.
Sound energy is the energy produced by vibrating sound waves.
13.
Frequency is the number of cycles or completed alternations per unit time of a wave or
oscillation.
14.
Option B
15.
Option B
16.
Option D
17.
Music is a sound that has rhythm, pitch and volume.
18.
Intensity determines the loudness.
19.
We inform each other on time with the lunch whistle, danger with the fire alarm or the police whistle, happiness or sadness with music, and so on.
20.
Option C