- #1
FerPhys
- 16
- 0
Hello everyone, please help me understand this.
We were given a conceptual question that says "A sound wave goes from the air into the ocean. Which of the following applies (circle all that apply):
a)its intensity increases b) its wavelength decreases c) its frequency increases
d)its frequency remains the same e) its velocity decreases.
My answers were A & D.
I was correct on D but my professor said A was wrong. He didn't really give the class much of an explanation but when I asked him personally he said; you're saying intensity increases, where does the "new energy" come from? intensity=power/area
At the time I didn't really have an answer so I took him to be correct but after reviewing I still think I'm correct.
Since Intensity = 2π2ρƒ2v∆x2max and the density of water is greater than that of air, frequency remains constant, and velocity increases in water (I have no clue where Δx2max comes into play) I chose intensity to be increasing. Now, I think I found the flaw in his logic. He asked, "where is all that energy come from to make the intensity greater"? He believes intensity measures a quantity of how much energy is transfer but it is actually THE rate at which energy is transferred in an area! Therefore, from the original question wouldn't I be correct to say that the intensity in water increases? Meaning energy is transferred at a higher rate/area?
Thoughts?
We were given a conceptual question that says "A sound wave goes from the air into the ocean. Which of the following applies (circle all that apply):
a)its intensity increases b) its wavelength decreases c) its frequency increases
d)its frequency remains the same e) its velocity decreases.
My answers were A & D.
I was correct on D but my professor said A was wrong. He didn't really give the class much of an explanation but when I asked him personally he said; you're saying intensity increases, where does the "new energy" come from? intensity=power/area
At the time I didn't really have an answer so I took him to be correct but after reviewing I still think I'm correct.
Since Intensity = 2π2ρƒ2v∆x2max and the density of water is greater than that of air, frequency remains constant, and velocity increases in water (I have no clue where Δx2max comes into play) I chose intensity to be increasing. Now, I think I found the flaw in his logic. He asked, "where is all that energy come from to make the intensity greater"? He believes intensity measures a quantity of how much energy is transfer but it is actually THE rate at which energy is transferred in an area! Therefore, from the original question wouldn't I be correct to say that the intensity in water increases? Meaning energy is transferred at a higher rate/area?
Thoughts?