Sound Energy
What is the source of sound energy?
Sound energy originates from an object or substance that is vibrating.
What type of energy is sound?
Sound is a form of kinetic mechanical energy.
Can sound travel in a vacuum?
No — sound is a mechanical wave, so it needs a medium (air, water, or solid) to travel through.
What are the two main types of mechanical waves?
Transverse waves and longitudinal waves.
In a transverse wave, how do particles move?
Particles move perpendicular (up and down) to the direction the wave travels.
In a longitudinal wave, how do particles move?
Particles move parallel (back and forth) to the wave’s direction.
What does the horizontal central line in a wave diagram represent?
Axis or resting position
What is Amplitude
The maximum distance a particle moves from the rest position (height of the wave).
What is Wavelength
The distance between two consecutive crests
What is the formula for the speed of sound?
velocity = frequency times wavelength
In a given medium, what happens to sound velocity?
It stays constant, so frequency and wavelength change inversely.
What happens if wavelength increases?
Frequency decreases — the sound has a lower pitch.
What is an echo?
A reflected sound wave that’s heard separately after the original sound.
Why does the sound need to travel that distance for an echo?
So there’s enough time delay for the reflected sound to be heard separately from the original.