Waves Flashcards
What do waves transfer?
Energy but not matter
What does a mechanical wave travel through?
A medium
Examples of mechanical waves
Sound waves, water waves, waves on springs and ropes, seismic waves from earthquakes
What are mechanical waves caused by?
Vibrations
What do electromagnetic waves travel through?
A vacuum
What is the speed of light?
300,000,000 m/s
Examples of the electromagnetic waves
Light waves, radio waves, microwaves
What are oscillations?
Vibrations of the wave
In longitudinal waves which way do the oscillations travel?
Parallel to the direction of energy
In transverse waves which way do the oscillations travel?
Perpendicular to the direction of energy
What is frequency?
Number of waves passing a fixed point per second
What are the units for frequency?
Hertz (Hz)
What is the equation of period?
Period = 1 / frequency
What is period?
Measure of time that tells us how long it takes to pass a fixed point
What is the equation for the speed of a wave?
Speed = frequency x wavelength
What is the amplitude?
The maximum displacement of a point on a wave from its undisturbed position
What is the law of reflection?
The angle of incidence is equal to the angle of reflection
What is refraction?
The bending of light rays at the interface of dissimilar substances
What happens when a wave interacts with matter?
Reflection, refraction, absorption, transmission
What do oscilloscopes show?
An image of a sound wave which has been converted into an electrical signal
What is the amplitude like if a sound is loud?
Big
What is the amplitude like if the sound is soft?
Small
What is loudness measured in?
Decibels (dB)
How do you investigate speed of sound?
- Measure 100m
- Person hits wood blocks together when you see this start timer
- Stop timer when you hear the sound
- Record result
- Repeat readings, identify anomalies, calculate mean to increase accuracy
