Waves Flashcards
(16 cards)
What are transverse waves?
Waves where the oscillations are 90 degrees to the direction of energy transfer and are created through perpendicular motions
What are longitudinal waves?
Waves where the oscillations are are parallel to the direction of energy transfer
What are the units for frequency?
Hertz
How do you measure a wave?
What is the period of a wave?
Time taken for one complete wave to pass a point
Measured in seconds
What is a similarity between transverse and longitudinal waves?
They both have an energy source
Why do you see lightning before you hear it?
Because light travels faster than sound so the light reaches your eyes and then sound reaches your ears after. The closer you are to the lightning the shorter the gas between the lightning and thunder
What does opaque, translucent and transparent mean?
Opaque- something you are unable to see through as no light is transmitted
Translucent- something you are slightly able to see through as some light is transmitted
Transparent- something that is completely see through as it transmits most light
What is the law of reflection?
The angle of incidence is equal to the the angle of reflection
How is light refracted when it moves from a less dense to a more dense medium?
It will move closer to the normal than the ray of incidence
How does light refract when it moves from a more to a less dense medium?
It gets further from the normal than the ray of incidence?
What causes light to refract?
When light passes into a substance with a different density
What is the electromagnetic spectrum in order of longest to shortest wavelength?
Give a use of each
Radio- radar
Microwave- cooking
Infared- tv remote, night vision
Visible- sight
Ultraviolet- tanning salons
X-ray- medical imagery
Gamma- radiotherapy, sterilisation
Why does light refract?
Because the wave changes in speed as it moves into different mediums
For example if it went from air to glass it will move more slowly and refract
What happens to the wavelength of light when it refracts from a less dense to a more dense medium?
It decreases
What happens to the frequency in refraction?
It stays the same
