• Support PF! Buy your school textbooks, materials and every day products Here!

Sound intensity, given frequencies

  • Thread starter Radian
  • Start date
  • #1
1
0

Homework Statement



The intensity of a sound wave at a fixed dis-
tance from a speaker vibrating at 1.31 kHz is
0.894 W/m^2.
Determine the intensity if the frequency is
increased to 2.33 kHz while a constant dis-
placement amplitude is maintained.
Answer in units of W/m^2

Homework Equations



I=(P/4pi*r^a) and L = 10log(I0/I1)

The Attempt at a Solution



I tried a proportion with frequency over intensity to where I did (1.31)/(.894) = (2.33)/(x) and got 1.59 but the internet program said it was wrong (I have 6 more tries). I then looked at my equation relating intensity to power and area which is the first equation listed above which is one of the many equations that we have learned in class. It seems like the most ideal equation but the problem is that I'm not given power and I don't know how to relate power to frequency. My guess is that maybe you solve for some sort of radius with the first part of the problem and then use that radius in the second part since it says that the displacement doesn't change. Thanks.
 

Answers and Replies

  • #2
TSny
Homework Helper
Gold Member
12,538
2,956
Roughly: Intensity [itex] \propto [/itex] Energy [itex]\propto[/itex] velocity squared [itex]\propto[/itex] frequency squared
 

Related Threads on Sound intensity, given frequencies

Replies
2
Views
22K
Replies
17
Views
1K
Replies
0
Views
2K
Replies
15
Views
4K
Replies
3
Views
58K
  • Last Post
Replies
6
Views
4K
  • Last Post
Replies
2
Views
1K
  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
1
Views
2K
Top