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Christ Church
Church of England Primary School

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Science: String Telephones

In Year 4 we have been looking at sound in science.

On Thursday, we made our own telephones using string and plastic cups. It was amazing how clear we could hear each other through them.


We then tried an experiment to see if we all crossed strings would we be able hear one person talking. Most of us were able to hear the person even though our strings were just touching and not tied together.


How do the telephones work?

The string and the cups are solid, so the particles are much closer together than the particles in the air, which is a gas.


The sound energy can travel from particle to particle far easier in the solid string telephone. so the sound of a voice is louder over the same distance than it is in the air.