science Flashcards
what is a wave?
the transfer of energy without matter
what are the 2 types of waves
longitudinal and transverse
what is a longitudinal wave
a wave that’s energy goes back and forth.
what is a transverse wave
a wave that’s energy goes up and down
what type of wave is a light wave.
tranverse
what is the wave length
1 peak + 1 trough, 2 peaks or 2 troughs
what is the wavelength unit of measurement
lambda
what is the peak of a wave
the highest part of a wave
what is the trough of a wave
the lowest part of the wave
what is the amplitude of a transverse wave
the height of the crests above the middle position
what is frequency
frequency is the number of something in a unit of time
what is hertz/hz
the number of waves per second
when a longitudinal waves are very close together they are called:
compressions
when a longitudinal waves are very far from each other they are called:
rarefactions
wavelength in light determines
colour
amplitude in light determines
brightness
wavelengths are measured in
metres
v in the wave equation is
velocity/speed in metres per second
f in the wave equation is
the frequency in hz
lambda in the wave equation is
the wavelength in metres
the wave equation shows the
speed of a wave
the wave equation is
v=flambda
time period is
T=1/f
the time period is measured in
seconds
hz =
1/second
heat transfer occurs in three ways
conduction convection radiation
what is conduction
this happens through the vibration of the heat particles that vibrate ,more in turn.
what is convection
due to the heat higher vibration, it moves cold air out of the way and quickly fills the room
what is radiation
using heat waves to transfer heat WITHOUT OTHER PARTICLES
state the temperature on the Fahrenheit celsius and Kelvin scales at which water freezes
0c 32fahrenheit 273kelvin
the speed of sound through air at 0 degrees c in metres per second
331
the speed of sound through air at 18 degrees c in metres per second
342
the speed of sound through water in metres per second
1440
the speed of sound through wood in metres per second
4500
the speed of sound through steel in metres per second
5100
the speed of sound through glass in metres per second
5200
how many Australians have a hearing disability
1 mil
light is a form of what energy
electromagnetic radiation
when light hits a surface it may:
be transmitted, reflected or absorbed.
what is a translucent material
some light reflected, and some light passed through.
what is a transparent material
almost all light is transmitted through the substance. a clear image can be seen through it.
what is a opaque material
light is either reflected from or absorbed into the substance, and no light is transmitted. no image can be seen through it.
what is diffuse reflection
the surface of the objects are quite rough when viewed up close. these surfaces reflect light in many directions, and do not form an image.
what is the law of reflection
angle of incidence(i) = angle of reflection(r)
what is refraction
the light bending due to warped glass
what is a convex lens
a lense that bulges outwards
what is a concave lens
a lense that bulges inwards
what is a real light ray
a image that forms when light rays cross
what is a virtual light ray
a image that forms when light rays appear to cross but don’t.
what is the law of refraction
n_1 \sin \theta_1 = n_2 \sin \theta_2
what is the depth illusion
when part of the refraction of your eyes is reflected and it seems as if something is closer than it actually is
