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

Physics of Sound Waves

Note: I'm sorry if I have to use the template, but I already have the solution, I just do not understand it and need help understanding it.
1. Question: A firework explodes at a 40 metre height and gives off a bang which measures at 100 dB at ground level. What is the power of the sound that comes off the firework?

This is the solution:

xlcdqf.png

I understand what is going on, for the most part.
What I do not understand exactly is at the second part the "100 dB" becomes 10^100dB/10 which removes the log. How? I understand that the exponent is 10 in "10*log" but I don't really understand how the 10 comes from in the exponent of the 10 itself.

Any help would be appreciated. Thanks!
 

Attachments

George Jones

Staff Emeritus
Science Advisor
Gold Member
7,229
781
What I do not understand exactly is at the second part the "100 dB" becomes 10^100dB/10 which removes the log. How? I understand that the exponent is 10 in "10*log" but I don't really understand how the 10 comes from in the exponent of the 10 itself.
If ##A = B \log_{10} C##, then ##A/B = \log_{10} C##, and ##C =##?
 

Want to reply to this thread?

"Physics of Sound Waves" You must log in or register to reply here.

Related Threads for: Physics of Sound Waves

  • Posted
Replies
1
Views
5K
  • Posted
Replies
1
Views
3K
Replies
8
Views
397
  • Posted
Replies
1
Views
1K
  • Posted
Replies
4
Views
4K
  • Posted
Replies
5
Views
5K
  • Posted
Replies
3
Views
722
  • Posted
Replies
2
Views
4K
Top