1.) A sound wave with wavelength 0 and frequency f 0 moves into a new medium in

Question

1.) A sound wave with wavelength 0 and frequency f0 moves into a new medium in which the speed of sound is v1=4.00v0.

What is the new wavelength of 1?

What is the new frequency of f1?

Which one of the following statements is true?

2.) Which one of the following statements is true?

Both the intensity level (in dB) and the sound intensity can be negative. The sound intensity can never be negative, but the intensity level (in dB) can be negative. Both intensity level (in dB) and sound intensity obey inverse-square distance laws. Both the intensity level (in dB) and the sound intensity can never be negative. The intensity level (in dB) obeys an inverse-square distance law, but the sound intensity does not.

Explanation / Answer

1.) When the sound wave changes medium, the frequency remains unaffected whereas the wavelength and the speed change.

So, new frequency f1 = fo

We know that, frequency = speed of sound / wavelength

so, old frequency = old speed of sound / old wavelength => fo = vo / o

So, new frequency = new speed fo sound / new wavelength = > f1 = fo = 4vo / 1

1 = 4vo / fo = 4 ( vo/fo  ) = 4 o

So, the new wavelength 1 = 4o

2.) Sound intensity level is given by I (dB) = 10 log (I/ Io ) where I is the intensity of the sound wave,

and Io = 10-12 Watt/m2   is the reference intensity.

So, If I < Io  (which is possible with much smaller intensity) , Sound intensity level will be negative, but intensity itself cannot be negative.

So, the answer is b.) The sound intensity can never be negative, but the intensity level (in dB) can be negative.

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.