Practise IB Physics HL C.4 by analysing harmonic modes, resonance conditions and standing-wave data across strings, pipes and coupled systems.
A loudspeaker emits sound of frequency 210 Hz into a pipe with one open and one closed end. The diagram shows a representation of the standing wave established in the pipe.
The length of the pipe is 1.20 m .
Outline how the standing wave is formed in the pipe.
Determine the wavelength of the wave.
The solid line represents the standing wave at time t and the dotted line represents the standing wave at an instant later. The dot is the equilibrium position of a particle P in the pipe. The up arrow indicates displacements to the right and the down arrow displacements to the left.
On the diagram, draw
a dot to indicate the approximate position of P at time t,
an arrow to indicate the velocity of P at time t.
The frequency of sound is reduced to 140 Hz . Explain why a standing wave will not be formed in the pipe.
