honors physical science chapter 9 test

wave

repeating disturbance that transfers energy. The matter does not move along with the wave.

transverse waves

have particles move perpendicular to the wave motion.

EX: ocean waves, ropes, crowd waves

longitudinal waves (compression wave)

have particles that move parallel to the wave motion. EX: sound waves and seismic waves

crests

highest point on the wave (only in transverse waves)

troughs

lowest point on a wave (only in transverse waves)

compression

dense region (only in compression wave)

rarefactions

less dense regions (only in compression wave)

wavelength

The distance between one point on the wave to the nearest point just like it. (measuered in meters)

Amplitude

height of a wave from middle to far point. (measured in meters)

mechanical waves

require a medium such as water, a rope, air, earth, etc.

electromagnetic waves

can travel through a medium or empty space. EX: light, radio wave, microwaves etc.

period

amount of time it takes for one wave to pass a given point. (measure in seconds)

frequency

number of wavelengths that pass a point in one second (label is Hz=hertz)

wave speed

related to period and frequency as both relate to time. speed of wave is wavelength divided by the period. Or frequency times wavelength.

transmission

when a wave continues straight through an object. happens through windows.

refraction

when a wave is bent as it goes through an object. this is why objects look different through water.

reflection

when a wave bounces off a surface at the same angel the wave hit the surface. This is what occurs with mirrors

absorption

when a wave is taken into an object. This is why black clothing is hot in the summer

diffraction

when a wave bends around objects. When sound waves do this we are able to hear around corners.

scattering

when a wave is sent in many different directions. Our atmosphere scatters blue light well when overhead. At an angle it scatters longer wavelengths such as red better.

interference

when waves overlap. This only happens with mechanical waves. When sound waves interfere they increase the volume or cancel it out.

How is sound produced?

when air molecules vibrate creating longitudinal (compression) waves.

medium density

refers to how compact a material is. more compact materials such as solids, move sound waves faster while gas moves sound waves slower.

temperature

allows particles to move faster when heated, so sound moves faster at higher temperatures

elasticity

the ability of a material to return to its original state. waves will travel quicker through objects that are more elastic like rubber and clay

what is speed of sound?

343m/s

auricle

part of the ear you see

ear canal

channel the waves to tympanic membrane(ear drum)

tympanic membrane (ear drum)

vibrates like head of a drum. Moves bones in the middle ear

middle ear

made up of three smallest bones in your body (malleus, incus, and stapes) act like levers to transferring the pulsing of the ear drum to move fluid in the inner ear

malleus (hammer)

connected to the incus

incus ( anvil)

connected to the stapes (stirrup)

oval window

starts the inner ear. vibrates the liquid into the cochlea

cochlea

lined with hairs that resonate at certain frequencies, when the hairs resonate they send electrical pulses to the auditory nerve.

auditory nerve

interpret the sounds the vibrations in the brain as sound

semicircular canals

attached to the cochlea, contain fluid and help sustain balance in all three plains.

intensity (loudness)

amount of energy in a wave. more intense = higher amplitudes.

pitch

how high or low a sound seems to be. determined by frequency in hertz.

constructive interference

adding the waves increasing the intensity

destructive interference

cancels out parts of each wave, making a smaller wave and decreasing intensity.

standing wave

when a wave appears to be standing still

timbre

the quality of sound

fundamental frequencies

first harmonic and main note you hear

overtones

start and end their wave at the same points as the fundamental frequency

resonance

when an object vibrates from other vibrations matching the objects fundamental frequency

electromagnetic waves

waves that can pass through a median or empty space

nonionizing radiation waves

cause atoms to vibrate, shift, or become excited but are not harmful. tend to warm up the material they come intact with. (visible light, microwaves, radio waves, and infrared waves).

ionizing radiation waves

have enough energy to excite atoms in the material enough to remove tightly bound electrons from the atom creating ions, which can be harmful.

photon

will bump electrons offmetal

additive colors

colored lights. adding colors all together makes white light, all colors subtracted makes black light.

subtractive colors

pigments, paints, inks, and dye.all colors combined create black, all colors subtracted creates white.

light primary colors

red, green, blue

colored paints or pigments primary colors

magenta, cyan, yellow, and black