Waves

• A sound wave is a longitudinal wave that consists of compressions and rarefactions in a medium.
• The hairs each come from a nerve cell.
• Wavelength is the distance between the same points on two consecutive waves.
• Amplitude is the distance from equilibrium line to the maximum displacement (crest or trough).
• Frequency is the number of waves that pass a single point per second.
• Period is the time taken for a whole wave to completely pass a single point.
• Velocity equals frequency times wavelength, represented as 𝑣𝑣 = 𝑓��𝑓𝑓.
• Period is inversely proportional to frequency, represented as 𝑇𝑇 = 1/��𝑑.
• Smaller period, higher frequency, greater velocity.
• Transverse waves, such as light, have peaks and troughs and vibrations are at right angle to the direction of travel.
• Longitudinal waves, such as soundwaves, have compressions and rarefactions and vibrations are in the same direction as the direction of travel.
• Wavelength, amplitude, frequency, and period are all physical properties of waves.
• Compression forces the eardrum inward.
• Each hair is sensitive to different sound frequencies, so some move more than others for certain frequencies.
• The smoother the surface, the stronger the reflected wave is.
• The light will be absorbed, and then reemitted over time as heat.
• Vibrations of the bones transmitted to the fluid in the inner ear.
• The angle of incidence equals the angle of reflection.
• The electrons will absorb the light energy, then reemit it as a reflected wave.
• Sound waves can travel through solids causing vibrations in the solid.
• Waves will reflect off a flat surface.
• Rarefaction forces the eardrum outward, due to pressure.
• As the fluid moves due to the compression waves, the small hairs that line the cochlea move too.
• It can still refract, but the process of passing through the material and still emerging is transmission.
• The eardrum vibrates at the same frequency as the sound wave.
• Waves will pass through a transparent material.
• If a material appears green, only green light has been reflected, and the rest of the frequencies in visible light have been absorbed.
• The small bones act as an amplifier of the sound wave the eardrum receives.
• Rough surfaces scatter the light in all directions, so they appear matt and not reflective.
• Compression waves are thus transferred to the fluid (in the cochlea).
• As it travels down, it is still a pressure air wave.
• Light will reflect if the object is opaque and is not absorbed by the material.
• The outer ear collects the sound and channels it down the ear canal.
• The more transparent, the more light will pass through the material.
• The sound waves hit the eardrum, a tightly stretched membrane which vibrates as incoming pressure waves reach it.
• If the frequency of light matches the energy levels of the electrons, the light will be absorbed by the electrons and not reemitted.
• When a certain frequency is received, the hair moves a lot, releasing an electrical impulse to the brain, which interprets this to a sound.
• Humans cannot hear below 20Hz or above 20kHz.
• In the cochlea, the hairs attuned to the higher frequencies die or get damaged.
• The hairs can be damaged due to constant loud noise or chemotherapy.