2. What we will do today Carry out experiments on sound waves. State that for sound to be produced an object must vibrate. State that sound is a wave which transfers energy. State that the frequency of a sound is the number of waves produced in a second and is measured in a unit called Hertz. State how sound travels. Investigate if sound can travel through solids, liquids and gases. State what is meant by a vacuum. Investigate if sound can travel through a vacuum.

3. Sound Waves For sound to be produced an object must vibrate. Sound is a wave which transfers energy. The frequency of a sound is the number of waves it produces in one second. Frequency is measured in Hertz (Hz).

4. Sound Travels Today we are going to investigate how sound travels. What apparatus could you use to find out whether or not sound travels through solids, liquids and gases?

5. Sound Travels Copy and complete the following table. MediumDoes sound travel? Example GasYesOur voice travels through the air Liquid Solid Vacuum

6. Sound Travels Sound can travel through solids, liquids and gases. Sound cannot travel through a vacuum.