Describe how a loudspeaker cone produces sound.

State the limits of the frequency range of sound waves that can be heard by a healthy human ear. Include the correct unit.

Two students attempt to measure the speed of sound in air. They stand a measured distance of 75 m apart. One student strikes a metal triangle with a rod. The second student starts a stopwatch when they see the strike and stops it when they hear the sound.

Explain why the calculated speed of sound from this experiment is likely to be highly inaccurate.