Year 4 Science
This week in science, Year 4 had a discussion about how sound waves travel and how the particles of whatever they are travelling through vibrate, or move quickly on the spot. The further the vibrations travel, the more they spread out. As they spread out through more and more particles, the vibrations become smaller and smaller. This causes the sound to get quieter and quieter.
After our discussion the children went on to make string telephones. 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 your voice is louder over the same distance than it was in the air.