Waves Flashcards
What are waves?
Waves transfer energy. Waves may be either transverse or longitudinal. Waves can be reflected, refracted and diffractive. Waves undergo a change in direction when they are refracted at an interface.
What type of wave are electromagnetic waves?
Transverse
What type of wave are sound waves?
Longitudinal
What type of waves are mechanical waves?
They can be longitudinal or transverse.
What is an electromagnetic wave?
They all travel at the same speed though a vacuum and they form a continuous spectrum. Radio waves, microwaves, infrared and visible light can be used for communication.
What are longitudinal waves?
They areas of compression and rarefaction.
What is the normal?
A construction line perpendicular to the reflecting surface at the point of incidence.
What is the angle of incidence?
It is equal to the angle of reflection
How can the image produced in a plain mirror be described?
Virtual, upright and laterally inverted
What kind of waves are sound waves?
Longitudinal, they also cause vibrations in a medium, which are detected as sound
What is the pitch of a sound?
It is determined by its frequency and loudness by its amplitude
What are echoes?
Reflections of sounds
What is the Doppler effect?
If a wave source is moving relative to an observer there will be a change in the observed wavelength and frequency.
What is redshift?
There is an observed increased in the wavelength of light from most distant galaxies. The further away the galaxies are, the faster they are moving, and the bigger the observed increase in wavelength.
How does redshift support the Big Bang?
Showing that the universe is expanding and that the universe began from a very small initial point.
