Immitance Flashcards
define immitance
how well energy flows through a system
acoustic immittance- specific to acoustics
define impedance
Opposition to the flow of energy (how well it doesn’t flow)
define admittance
Ease with which energy flows through a system (how well it does flow)
Hearing range curves - why we have that shape on curve
ossicle size
How many components does immitance have?
3 (2 frequency dependent one not)
What are the 3 immitance components and which are frequency dependent and frequency independent
Mass reactance
opposition to high frequency motion
Stiffness reactance
opposition to low frequency motion
Resistance
Opposition to energy flow
Frequency independent ((neutral; same at all frequencies)
large mass
opposes high frequency because it cannot vibrate fast
small mass
opposes low frequency because it cannot vibrate slow
large stiffness
opposes low frequencies because it cannot vibrate slowly
Will increasing mass make an object vibrate more slowly or more quickly?
more slowly
Will increasing stiffness make an object vibrate more slowly or more quickly?
more quickly
Explain why smaller animals have better high frequency hearing, based on ossicle size.
they have better high frequency hearing because they have smaller ossicle size so they vibrate faster, less opposition (resistance) to high frequency vibration
Select one: broadly tuned/narrowly tuned systems are efficient sound transducers.
broadly tuned
Which is better at sound transducer?
broadly tuned system
would it be preferred to listen out of a small speaker or a movie theater?
movie theater because it is more broadly tuned system
What gives us a low frequency hearing loss?
ossicular adhesions, unequal pressure on both sides of tm, fluid in ears because it has an increase in mass
what gives us a high frequency hearing loss?
Thickening of the tm
Mass in ME or EAC
Pus, blood, or serous fluid in the middle ear
Many otitis media cases begin as stiffness factors and move to mass factors
Earplug in ear canal!
because it causes an increase in mass and decrease in stiffness
What influence do stiffness and mass have on the characteristics of typical human hearing?
they have an equal influence = no influence
What kind of hearing loss would result from an increase in stiffness?
low frequency hearing loss
What kind of hearing loss would result from an increase in mass? What is the one example you should remember from the list of examples?
high frequency hearing loss
earplug stuck in the ear canal
What kind of hearing loss would you see with impacted cerumen?
high frequency hearing loss because there is an increase in mass?
