How We Hear
Class 8 Science: sound (the human ear)
Send a sound into the ear and follow it: ear canal, eardrum, tiny ear bones, cochlea and the nerve to the brain. Try loud and high-pitched sounds.
Words to know
- Eardrum
- A thin stretched membrane that vibrates when sound reaches it.
- Ear bones
- Three tiny bones (hammer, anvil, stirrup) that pass the vibrations on.
- Cochlea
- A snail-shaped tube in the inner ear that turns vibrations into nerve signals.
- Pitch
- How high or low a sound is. It depends on the frequency.
- Decibel (dB)
- The unit for loudness. Above 85 dB for a long time can harm hearing.
Quick check
Answer 3 questions to check what you learned.
Try at home
Stretch a piece of a balloon over a cup and put a few grains of rice on it. Shout near it, then bang a steel plate near it. That is how your eardrum moves.