light and sound

Light Energy

Energy is the ability to do work or make something happen

Reflectors

Objects good at bouncing light off their surface

Luminous vs Non luminous

Luminous objects give off their own light and non luminous don’t

Opaque

Light can’t pass through

Transparent

Light easily passes through

Translucent

Only some light passes through

Reflect vs Refract

Reflect-light bouncing off something and refract is when light passes through an object and bends/changing direction as it passes through the object

Photons

The basic particle of light energy

Sound Energy

The movement of energy through something (solid/liquid/gas) as a wave

Longitudinal Wave

A pressure or compression (particles squashed together) wave such as sound.

Transverse Wave

Used to help describe a sound pressure wave (longitudinal)

Compression

Particles pushed closer together

Rarefaction

Particles pushed further apart

Crest

The peak of a T wave

Trough

The dip of a T wave

Amplitude

Larger amplitude= Louder Sound. Wave crest is higher the louder the sound.

Frequency (pitch)

How high or low the vibration sounds.   Wavelength shorter=Higher pitch

Echo

Sound waves hitting an object and reflecting back

Sonar

A technique using sound wave to detect and object or navigate

Electromagnetic Spectrum

All wavelengths of light including that not visible to humans

Visible Light

ROYGBIV-all the colours of the rainbow

VIOLET has the

VIOLET has the most energy (shortest wavelength/highest frequency wave)

Dispersion

The splitting of white light into ROYGBIV

Concave ( and Convex

Concave (converging) and Convex (diverging) mirrors.

Refraction

Light waves passing through an object bend as they change speed due to the density of the medium (solid, liquid, gas) changing. The object appears to bend.

Converging

Light rays come together

Diverging

Light rays spread apart

Eye order

Cornea, Pupil, Lens, Retina, Optic Nerve

Cornea

Transparent protective layer of the eye

Pupil

Opening in the centre of the iris that lets light reach the lens

Iris

Coloured part that is a muscle controlling the width of the pupil. Bright light=smaller hole

Lens

Convex lens focus light onto the retina cells at the back of the eye

Retina

The back lining of the eye that contains rod and cone cells to detect light and colour.

Optic Nerve

Carries signals from the retina to the brain

Radar

A technology that uses radio waves (light from electromagnetic spectrum) to reflect back off an object (echo)

Ultrasound

Sound waves (that humans cannot hear) used in medical technology to form an image

Echo Location

Using sound echos to find an object

Pinna

Funnels sound into the ear canal

Ear Canal

Direct sound wave to the eardrum and middle ear

Ear Drum

A thin membrane that vibrates when sound waves hit. They pass the vibrations to the ossicles

Ossicles

Small bones that vibrate and amplify (increase) the sound

Malleus

First and largest ossicle (hammer)

Incus

Second ossicle (Anvil) which transfers vibration to the stapes

Stapes

Third ossicle, and smallest bone in the human body. (Stirrup) It transfers vibration to the cochlea.

Cochlea

Is a spiral tube which contains liquid. Here the vibrations in the liquid are transformed into electrical signals.

Auditory Nerve

Transfers the electrical signals from the ear to the brain

Semicircular canal

Contains fluid and hairs. The hairs detect the liquid moving as the head move and helps with balance

White objects

Reflect all the light colours

Black objects

Absorb all light colours

Red objects appear red as they reflect red light into your eyes

Reflects only red light into your eyes and absorbs all other wavelengths present. If no red light is present to reflect the object will appear black.

The primary light colours

green, red and blue

the secondary colours

magenta, cyan and yellow

Mixing the primary light colours

Mixing the primary light colours gives you white light