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.