Find force (N) of atmosphere on area

[Calhoun295]

Homework Statement

Your eardrum has an area of about 53 mm2. Sounds become painful to your ear when the pressure variations that are involved in sound reach 200 Pa above and below normal air pressure. At this level, called the threshold of pain, how much force is exerted on your eardrum?

Homework Equations

Pressure=$$\frac{Force}{Area}$$

The Attempt at a Solution

F=PA
F= 101000N/m^2 (.053m^2)
F= 5353 N

I've tried normal atmosphere above and below 200Pa. The answer isn't correct according to wileyplus. I'm obviously doing it wrong, so what's wrong with my equation?

 

[tiny-tim]

Hi Calhoun295!

(try using the X² tag just above the Reply box )

F=PA
F= 101000N/m^2 (.053m^2)
F= 5353 N

I've tried normal atmosphere above and below 200Pa.

No, you'll have P_atm on one side of your eardrum, and P_atm ± 200 on the other side … net pressure = ±200.

 

[RoyalCat]

Also note that $$53 mm^2= 53 \cdot ((10^{-3} m)^2) = 53\cdot 10^{-6} m^2$$