# User Forum

Subject :NSO    Class : Class 5

Which one of the following will produce the sound with the lowest pitch, when you blow across the mouth of the test tube?

A

B

C

D

Was it a class v question?

## Ans 1:

Class : Class 5
ha you have copied

Class : Class 7

## Ans 3:

Class : Class 6
Ans A When playing a musical instrument that is a closed-end air column, such as the bottles in this activity, the pitch of the note that is made depends on the length of the air column. In other words, the pitch depends on how much water has filled up the bottle and how much empty space remains. This is because the pitch of the sound we hear depends on the frequency of the sound wave that can be created within the bottle's air. The shorter the air column (that is, the shorter the height of the air in the bottle) the higher the frequency. And the higher the frequency the higher the perceived pitch. This is why the empty bottle should have produced a sound wave with a lower frequency than the others and the bottle that was nearly full (three quarters full) should have made the highest pitch.

## Ans 4:

Class : Class 2
Ans A When playing a musical instrument that is a closed-end air column, such as the bottles in this activity, the pitch of the note that is made depends on the length of the air column. In other words, the pitch depends on how much water has filled up the bottle and how much empty space remains. This is because the pitch of the sound we hear depends on the frequency of the sound wave that can be created within the bottle's air. The shorter the air column (that is, the shorter the height of the air in the bottle) the higher the frequency. And the higher the frequency the higher the perceived pitch. This is why the empty bottle should have produced a sound wave with a lower frequency than the others and the bottle that was nearly full (three quarters full) should have made the highest pitch.