Two children make a toy telephone from two paper cups joined by a tight string. The string is attached to the base of each cup.
One child speaks into cup P. The other child holds cup Q to her ear and hears the voice.
Explain how the sound wave of the voice in the air inside cup P makes the string vibrate.
Explain how the vibrations of the string produce a sound wave that the second child hears.
The voice heard at cup Q has the same pitch as the voice at cup P.
Explain why.
Very high-pitched sounds are not heard clearly through the toy telephone.
Suggest why.
112 exam-style questions on Edexcel GCSE Physics 4.3 Sound, ultrasound and infrasound, covering 4.3.1 Sound waves, vibrations and the human ear, 4.3.2 Ultrasound and infrasound, 4.3.3 Uses of ultrasound and infrasound, and 4.3.4 Sound waves passing between media. Each one has a worked solution and a mark scheme showing where the marks go.