Homework Statement
the laws of refraction and reflection are the same for sound as for light. the speed of sound is 340 m/s in air and 1510 m/s in water. if a sound wave traveling in air approaches a plane water surface at an angle of incidence 12°, what is the angle of refraction?
Homework...
oh ok. thank you! I came to the conclusion of nine after your first post but that seemed almost too simple and i didnt want to embarass myself with a wrong answer haha. :)
so then... an increase of 10 dB means that the intensity of the sound is multiplied by a factor of ten right?
but I'm still confused about how to get the number of machines that can be added
Homework Statement
a noisy machine in a factory produces a decibel rating of 80 dB. how manyidentical machines could you add to the factory without exceeding the 90-dB limit?
Homework Equations
I=P/A and B+10log(I/I(sub)0) ... (I think)
The Attempt at a Solution I tried to find...