mechanical waves

mechanical wave

-wave motion that requires a medium (water, sound, slinkies…)

-from objects that vibrate

transverse wave

medium is displaced perpendicular to the direction of the wave

longitudinal wave

medium is displaced parallel to the direction of the wave

electromagnetic wave

no medium is needed (light, radio waves, x-rays…)

frequency

-the number of waves that pass a given point in 1 second of time

-high: high number of waves

-low: low number of waves

interference

-when 2 waves combine to make 1 wave

-the result of superposition (The displacement of a medium caused by two or more waves is the algebraic sum of the displacements caused by the individual waves)

parts of a transverse wave

up and down

highest point: crest

lowest point: trough

parts of a longitudinal wave

lines

highest energy: compression (bundled up part is in the middle)

lowest energy: rarefaction (bundle to bundle)

What do waves transfer?

energy

What determines the speed of a wave?

the properties of the medium

what amplitude can tell us

Displacement from the line of equilibrium to the height of a crest or trough.

loudness of a sound wave

proportional with the wave’s energy

HEIGHT!

Law of Reflection

The angle of incidence equals the angle of reflection

standing wave

-a pattern which results from the interference of two or more waves along the same medium

-characterized by positions along the medium which are standing still

-alternating pattern of nodes and antinodes

node

-the result of the meeting of a crest with a trough

-a point of no displacement

-dots

antinode

-over, under, over, under

-the result of a crest meeting a crest to form a supercrest and a trough meeting a trough to form a supertrough

Constructive interference

occurs when waves combine, resulting in a larger amplitude

Total/Complete Destructive interference

when waves come together so that they completely cancel each other out

Incomplete Destructive interference

when two waves overlap, their crests and troughs don't perfectly cancel each other out, resulting in a smaller wave

3 velocity wave equations

V=fλ

V=λ/T

V=d/t

What does it mean to be in phase?

-a wave front is the portion of the medium’s surface in which all particles are ___

-their peaks and troughs align, meaning they are at the same point in their respective cycles simultaneously, resulting in a constructive interference and a larger amplitude.

law of superposition

when two or more waves overlap, the resulting disturbance is the sum of the individual disturbances

refraction

Waves also may change direction – that change in direction of waves at the boundary between the two different media

diffraction

the bending of a wave around an obstacle

wave pulse

a single disturbance traveling through a medium

similar:
different:

more transmitted

more reflected

when waves interfere with eachother their _____ don’t get affected

energies