Sound and a bit more Flashcards
What is sound?
Sound is a longitudinal wave in which the wave energy travels in the same direction as the particles within the wave vibrate
What is the upper and lower range of hearing?
20-20000 Hz
Why do most humans hear a different range of frequencies?
Because the hair in ears gets damaged after hearing loud noises, which decrease the hearing range
In what state of matter does sound travel fastest?
Solid, then liquid then gas
How can it be shown that sound cannot travel through a vaccum?
By the bell jar experiment - put a bell in a jar without air. When the bell is rung, it cannot be heard because there are no particles that can vibrate as it is in a vacuum.
What is the formula for distance
Distance = speed x time
What is an oscilloscope?
A device with a microphone that can display sound waves on a graph
How can it be told if a sound wave is high or low pitch?
A noise with a higher pitch has a higher frequency
How can it be told if a sound wave is loud or quiet?
The higher the amplitude, the louder the noise
Why can different instruments play notes with the same amplitude and frequency, but the noise sounds different?
Because the shape of the wave is different
Why is a sound graph misleading?
Because sound waves are longitudinal, not transverse
What surfaces are better at emitting radiation
Dark Rough
What surfaces are best for absorption and reflection
Dark Rough for absorbing, Polished shiny for reflecting
What are the four different types of transfer?
Mechanical
Heat
Radiation
Electrically
What is the definition of renewable
Once used, can be replenished in a human lifetime.
