We have been learning how sound can travel through different materials – solids, liquids and gases.

We completed different experiments, making predictions then observed and listened to the results.

We learned that sound is an energy and travels in sound waves through vibrating molecules. As the molecules vibrate they carry the sound and pass to other molecules. We discovered that molecules in gases are spread out, molecules are closer together in liquids so sound travels faster. But molecules are the closest in solids so sound travels the fastest through solids.

We made our own gongs using string and spoons to listen to sound travelling through a solid (string).

We also created a hydrophone (plastic bottle) to listen to sounds under the water.

Finally we explored sound travelling through the air. We used rice to represent our air molecules so we could see the vibrations. We clapped, played a drum, played a triangle and played a speaker. We were amazed at how the rice moved around, especially when the speaker played – it jumped off the cup and danced around!