Waves Flashcards
What are waves?
Repeated vibrations of energy transfer
How is energy transferred?
By waves knocking neighbouring particles
What is a transverse wave?
Waves where points along the wave vibrate perpendicular to the direction of energy transfer
For a transverse wave
The energy transfer is in the same direction as the motion
They transfer energy but not particles of the medium
They move through liquids and solids but not gas
Some can travel through a medium (EM WAVES)
Examples of TRANSVERSE waves
- Ripples on the surface of the water
- Vibrations on a guitar string
- S waves
- EM waves
What are longitudinal waves?
Waves were the points along the wave vibrate parrallel to the direction of energy transfer
Properties of a longitudinal wave
- Energy transfer is in the same direction as motion
- Transfer energy but not particles of a medium
- CAN moves through liquids solids and gas
- They CANT travel through a vacuum as there are no particles
Examples of longitudinal waves
- Sound waves
- P waves
- Pressure waves
What is amplitude, wave length, wave frequency and time period?
Amplitude= Distance from the undisturbed position of the wave to the peak or trough - METRES
Wavelength= The distance from one point on a wave to the same point on the next wave - METRES (Symbol is lambada)
Wave frequency= The amount of waves that pass a point in one second - HERTZ
Time period= The time take for one wave to pass a point - SECONDS
Equation for wave speed
Wave speed = Frequency x Time
What do transverse waves have?
Peaks and troughs
What do longitudinal waves have?
Rarefactions and compressions
How are sounds waves transmitted?
Longitudinal waves work by the molecules vibrating and knocking into vibrating particles/molecules.
The more molecules that are present the more faster the wave can transfer energy
In what medium do sound waves travel fastest?
In solids and slowest in gases
Refraction of sound
When sound waves travel from a denser medium to a less dense medium their:
Wavelength increases
Frequency stays the same
Velocity increases
What is reflection?
When a wave hits a boundry between two media and doesnt pass through