Grade 4, term 3, Natural Science, Sound

What is sound? Different sound pitches. Reflected sound. What is noise pollution? Sound is a type of energy that is made by something moving. Solids, liquids and gases move, and these moving things cause vibrations.

When an iron chair is moved, you will hear the noise clearly. This noise comes from the vibration that the material is making when moved across the floor. Vibrations are small up and down movements, which you might not see.

Vibrations you might see or feel could be a cell phone ringing on the table or a gaming controller vibrating when you play a game. Energy from the vibrating material is then transferred to other things.

Sounds come in different pitches, it could be a high pitch or a low pitch. Some pitches are so high or low that human ears won’t pick it up, but some dogs can hear these different pitches. A high pitch could be someone whistling, a low pitch could come from a base guitar or base drum.

If you are swimming in the pool and hear your mom call from the side. It would not be clear, but you can hear a muffled noise.