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Sound
Science Junior Cert
| Question | Answer |
|---|---|
| Sound is a form of ________ | Energy |
| Sound is caused by what? | Vibrations |
| What does sound need in order to travel | Medium |
| To demonstrate that sound cannot travel without a medium what instrument would you place in a large sealed bell jar | Alarm clock |
| When the air is extracted from a bell jar with a ringing alarm clock, what happens | You cant hear it |
| What do you call a sound that bounces off an object | Echo |
| What do you call sound waves that have frequencies too high for humans to hear | Ultrasound |
| Name an application of ultrasound | To get image of baby in womb or on fishing vessels |
| What travels faster, light or sound | Light (340m/s) |
| What happens first, thunder or lightning | Lightning |
| What should workers do in a noisy work environment | Wear ear protection |
| How would you measure sound | Sound level meter |
| What is the unit of sound | Decibel dB |
| What level of sound could damage hearing if exposed to it on a regular basis | 85dB |
| What is the lowest level of sound that can be heard called | Threshold of hearing |