Science 4th grade | UNIT 4: Sound 4.7 High and low sounds
Pitch
A whistle makes a high-pitched sound. Thunder makes a low-pitched sound.
Slow vibrations produce a low-pitched sound. Fast vibrations produce a high-pitched sound.
Pitch is not the same as volume. The volume describes how loud or soft the sound is. For example, the sound of thunder is low-pitched but also loud.
Some sounds have such a high pitch or such a low pitch that we cannot hear them.
|
But other elephants can hear these sounds up to 7.5 km away |
String instruments
A guitar is a string instrument. Some strings are thicker than others. The guitar has pegs that you can use to make the string tighter or looser. You can also make the strings shorter by pressing them down. These things change the pitch of the notes. When you 'tune' a string instrument you change the pitch of the strings so that it is right for each string.
Activity 4.7 (Making high-pitched and low-pitched sounds on a guitar)
You will need: a guitar or other string instrument
Pluck the thick strings and the thin strings. Which strings make a higher pitched note? Tighten one of the strings by turning the peg. Now pluck the string. Does the sound have a higher or a lower pitch than before?
Loosen the string by turning the peg the other way. Predict the pitch of the sound when you pluck the string. Now pluck the string. Was your prediction correct? Now press the strings down on the neck with the fingers of one hand while you pluck the strings with your other hand. How does the pitch change?
|
|
|
|
Questions
1) Which factors affect the pitch of the sound of a stringed instrument?
2) Which has a higher pitch: a long string or a short string?
3) Which has a lower pitch:
a thin string or a thick string?