A Levels Physics

The diagram shows an air-filled pipe open at both ends. The length of the pipe is 1.00 m and the
lower surface of the inside of the pipe is covered with a layer of fine sand.
1.00 m
sand
When a source of sound of a single frequency is put near one end of the pipe, the air in the pipe
is found to resonate and a pattern in the sand shows that a standing wave containing three nodes
is formed within the pipe.
The speed of sound in air is 330 ms-!.
What is the frequency of the sound?
A 330 Hz
B 495 Hz
C 990 Hz
D 1320HZ


Waves | 2012 - O/N - 9702/13 | Q26