(a)[1]
State the meaning of the frequency of a sound.
(b(i))[2]
Given that the speed of sound in air is $330\,\text{m s}^{-1}$, calculate the wavelength of the sound in the air.
(b(ii)-1)[1]
The sound moves from the air into the glass. State what happens to its frequency.
(b(ii)-2)[1]
State how the speed of the sound changes.
(c(i)-1)[1]
Describe how the loudspeaker produces sound.
(c(i)-2)[2]
Describe the way sound is transmitted through air.
(c(ii))[1]
A pump is attached to the tube at the bottom of the glass bell-jar. The pump is then switched on and removes the air from the glass bell-jar. Explain why the volume of the sound heard outside the glass bell-jar decreases.