Science light and sound waves year 8 test revision

transverse wave

a wave that vibrates at right angles

longtudial wave

a wave where the particles vibrate paralell

frequency Hz

how often a wave happens in a certain amount of time

Amplitude

a measure of how tall/big the wave is

wavelength

the distance between two crests/troughs

Equilibrium

halfway between the crest and trough

crest

top of a wave

trough

bottom of a wave

complete cycle

complete cycle of a wave (crest to trough)

Kinetic energy

light

vacuum

a space that is almost entirely emtpy of matter

transmit

light passes through matter

reflect

light bounces off matter and changes its pathway

absorb

light is converted into heat and blocked

luminous object

an object that produces light

iluminated object

an object that reflects light

transparent

light passes through matter

translucent

light partially passes through matter (we can't clearly see through it)

opaque

matter blocks light

diffuse reflection

reflection from a rough surface

regular reflection

reflection from a smooth surface

normal line

line from the mirror surface

incident ray

a ray that travels from a source

reflected ray

a ray that bounces off the surface

medium

surface

short sighted correction

concave lens

longsighted correction

convex lens

rarefraction

when light bends/changes direction as it passes from one medium to another

concave mirror HINT-CAVE

enlarges images and bends inwards

convex mirror

shrinks images and bends outwards

what waves does sound travel as?

longtudial waves

what waves does light travel as?

transverse waves

can light travel through a vacuum

yes, light can travel through a vacuum

can sound travel through a vacuum

no

is space a vacuum

yes, space is a vacuum

range of sounds humans can percieve

20-20,000 Hz

electromagnetic spectrum

380-550 Nm (nanometers)

white light

mix of all seven light rays

concave focal point

in front

convex focal point

behind