Video and lesson investigations on the topic of sound. Key concepts include:
- Human sounds are made by using the vocal chords.
- Something must move for sound to be made.
- Sound is made by something vibrating.
- For example, when a bell rings, the sound vibrations vibrate the air, which, when it reaches our ears, make the tiny bones in our middle ear vibrate at the same frequency.
- This vibrating message is picked up by the auditory nerve connected to the inner ear, then transmitted to the brain where it is interpreted by the auditory centers.
- Altering the vibration changes the sound (it may make it louder or softer, or it may make a change intone or pitch).
- Sound travels away from the source of the sound in all directions and can travel through a gas, liquid or solid.
- The further the sound vibrations get from their source, the weaker they become