physics

define wave

a repeating disturbance or movement that transfers energy through matter or space

define medium

a form of matter through which the wave travels such as water, air, glass, gas, liquid and solid

what is the transverse wave

when the matter in the wave moves up and down at a right angle to the direction of the wave

what is the longitudinal wave

when the matter in the wave moves back and forth parallel to the direction of the wave

define wavelength

measure of distance so the units for wavelength are always distance units like meters, centimetres, millimetres

define wave frequency

number of waves that pass through a point in one second

define amplitude

the distance between the crest or the trough and the position of the medium at rest

define speed

how quickly the wave travels, described as fast or slow

define period

the time it takes for the wave to complete one cycle, measured in seconds

define wave equation

used to calculate speed, wavelength or frequency of a wave

what is sound wave

a mechanical disturbance that carries energy through a medium

what is the unit to measure the intensity of the sound

decibel

what are frequencies below 20Hz called

infrasound

what are frequencies above 20,000Hz called

ultrasound

what is a low pitch and a high high pitch

what is light wave

transverse electromagnetic energy that travel through a vacuum at high speed

what is transparent

when all light reaches through an object, its absorbed and reflected

eg. mirror

what is translucent

when some light passes through a object but not all and a light shadow

eg. tissue paper

what is opaque

when no light passes through by a object

difference between sound wave and a electromagnetic wave

sound- compressional wave(longitudinal), travels through all solid, liquid and gases but unable to travel through a vacuum, speed in air-330m/s

electromagnetic- transverse wave, able to travel through a vacuum but unable to travel through some substances(opaque), speed in air-300,000,000m/s

what is a mirror

a surface that reflects almost all incident light

what are two types of mirrors

plane mirrors- flat surfaces with a clear, smooth and a undistricted reflection

spherical mirrors- curved surfaces that reflects the surface of a hollow sphere

two types of spherical mirrors

convex and concave

difference between real images and virtual images in a spherical mirror

real- produces when light ray converge and intersect, can be projected and inverted

virtual- formed when light rays appears to diverge from a point and cant be projected

what is concave mirror

known as the converging mirror that curves inward and its light ray strikes and reflect from surface, they converge or come together at a specific point known as focal point

what happens when a concave mirror is placed very close to the object?

it forms a magnified, erect and virtual image, the image appears larger than the actual object and upright

what is convex mirror

often referred as a diverging mirror because when light ray strikes from surface, they diverge and spread out at a specific focal point

why is the space silent

no medium/particles required

define vibrating

something thats moving back and forth or from side to side with very short, quick and continuous movements

define electromagnetic spectrum

the full range of electromagnetic radiation

define particles

tiny pieces or units of matter that make up everything around us.

why is light waves faster than sound waves

-travels one million times faster than sound through air

-its an electromagnetic wave made of massless particles called photons. Because photons have no mass and dont require medium to travel

what conditions must occur to get a sound to reflect off a surface.

-Large Surface Area: must be larger than the wavelength of incoming sound

-Low Absorption: must be hard and non-porous so it doesnt absorb sound energy

-Low Transmission: must be dense enough to block the sound from passing straight through.

-Surface Smoothness: must be smooth, rough surfaces will scatter sound instead of reflecting it cleanly

define pitch

he auditory sensation of how "high" or "low" a sound is

define volume

amount of 3 dimensional space occupied by a substance of an object

How does the wave diagram change for increasing frequency

wave cycles get closer together more waves in the same amount of time, so the period gets shorter

How does the wave diagram change for increasing amplitude

the wave gets taller on the diagram, peaks rise higher and the troughs go lower, so the wave has a bigger vertical height from the middle line