Physics Test 2026

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What is a wave

a repeating disturbance that transfers energy from one place to another without transferring matter

What is a transverse wave?

which the medium moves at right angles to the direction of the wave

What is a crest

• the highest point of transverse wave

what is a trough

• the lowest point of transverse wave

what is a compressional/longitudinal wave

waves in which the medium moves back and forth in the same direction as the wave

what is compression?

• part of longitudinal wave where the particles are close together

what is rarefaction?

• part of a longitudinal wave where the particles are spread apart

what is the 3 properties that all waves have?

• wavelength

• amplitude

• frequency

what is wavelength

• the distance between one point on a wave and the exact same place on the next wave

• measured in metres

what is frequency?

• how many waves go past a point per second

• measured in hertz Hz

• higher the frequency, the more energy

• related to pitch on how loud or squeaky it is

what is amplitude

how far the medium moves from the resting position (the volume)

Draw a transverse wave

Pic

draw a longitudinal wave

picccc

formula for velocity

v = f λ

what is sound wave

• Sound waves are compressional waves that travel through the air through a series of compressions and rarefactions of vibrations

• Cannot travel in vaccum

what is sound intensity

• the energy that the sound wave possesses

• The greater the intensity of sound, the farther the sound will travel and the louder the sound will appear

unit for loudness

decibels dB

what is resonance

• occurs whenever a sound wave has the same frequency as the natural frequency

• the sound will cause the object with the same natural frequency to vibrate

how is frequency related to pitch?

• a high pitch sound has a high frequency

• for e.g. a girl screaming has a high pitch but a fog horn has a low pitch

why can’t sound travel in space?

• since sound is a mechanical wave requiring a medium to virbate on but space is a vacuum

what is doppler effect

• apparent change in frequency detected when the sound is moving relative to the hearer

what is echolocation?

• biological sonar system that some animals have

• emit sound waves to navigate and hunt and listen to the returning echos

• can help reveal size and shape of objects as well as distance, speed, and direction

what is infrasound

refers to frequencies below our hearing range

what is ultrasound

refers to sound waves above our hearing range

why does sound travel the fastest in solids?

• fastest in solids and slowest in gas

• because in soolids the particles are packed together (higer density) allowing vibrations to pass on from one molecule to another quickly

what is sonar

used in oceanography to map the seafloor timing how long a sound pulse takes to bounce back

what is tinnitus

the perception of ears ringing without an external sounds

symptoms of tinnitus

ringing, buzzing, hissing in the ear without external sounds

technological scientific use

ultrasound- used for safe medical imaging without using dangerous x-ray radiation

sonar- need for safe ship navigation and mapping ocean floor for resources or research

what are the classes of electromagnetic radiation?

• radio, infrared, visible light, ultraviolet, xrays and gamma rays

• ordered from longest (radio) to shortest (gamma rays)

how does light behave like a wave

when it bends around corners (diffraction)

how does light behave as a particle

like a particle (photon) when it hits a solar panel to create electricity

what is transparent

• when all lights go through the material

• glass, clear water

what is translucent

• when some of the light passes through and casts a light shadow

• vegetable oil, eyelid, thin tissue

what is opaque

• light is blocked and casts a dark shadow

• mirrors, rock, cardboard

what is the law of reflection

• states thtat the angle at which light hits a surface (incidence) equals the angle it bounces off

what is the normal line

dotted line drawn at 90 degrees to the mirror surface to measure these angles

characteristics of a virtual image

• upright and appears to be “behind” the mirror, but it cannot be projected onto a piece of paper.

• eg own reflection in a standard bathroom mirror

how do convex and concave mirrors differ

• convex- mirrors curve outward and are used as security mirrors in shops to see a wide area

• concave mirrors curve inward like a bowl and are used in makeup mirror to magnify your face

what is refraction and how does desnity affect it

• refraction is the bending of light as it moves between materials of different densities

• when light moves into a denser medium (like moving from air into glass), it slows down and bends towards the normal line

• when light moves into a less dense medium (like moving from glass to air), it speeds up and bends away from the normal.

• eg. straw looking broken/ bent in water

what is the difference between convex and concave lenses

• convex- thicker in the middle and converges light to a single focus point

• concave- lenses are thinner in the middle and cause light rays to diverge/ spread out

what is total internal reflection (TIR)

• happens when light hits a boundary at a very steep angle (greater than the critical angle_ and reflects entirely back into the material

• this is how high-speed internet data travels through fibre optic cables

what is visible spectrum

• small part of the electromagnetic spectrum that human eyes can see

• red, orange, yellow, green, blue, indigo, and violet.

• red has the longest wavelength, while violet has the shortest.

• they look white when all combined

what is normal line

• imaginary line drawn perpendicular to the surface of the mirror at the point where the light hits

• all angles are measured between the light ray and this normal line.

what is a medium

any substance or material through which light or sound can travel in

refracive index

• a value that describes how much a medium slows down light;

• a higher refractive index =material is more optically dense and light will bend more when entering it

refractive ray

the ray of light that has entered a new meium and changed direction

angle of refraction

• angle between refracted ray and the normal line

lens

• transparent piece of glass or plastic with at least one curved surface that refracts light rays to form an image

converge

when light rays move towards each other and meet at a single point, usually caused by a convex lens

focus (focal point)

the specific point where light rays that were travelling parallel to each other meet (converge) after pssing through a lens

focal length

distance between the center of the lens and the focus point

diverge

light rays move away from each other and spread out usually caused by a concave lens

virtual focus

point from which diverging light rays appear to originate when they are spread out by concave lens