wave question misuderstanding

[computerages]

hi every1~

 

I had the following question on one of my physics quiz, and I need some explanation on how'd you answer it.

 

"A bat detects an object 6 seconds after it emits a high frequency sound of 50,000Hz into aid at STP. How far away is the object from the bat?"

 

That's how I solved the problem:

 

[math]

d=t*v=6*331=1986m=d

[/math]

 

But my teacher said that I was supposed to use 3 sec. instead of 6. As far as I am concerned, it can be because of taking three sec. to go forward, and the other three to move back. I am not sure what it really means, but just a thought.

[swansont]

What you solved for was how far the signal traveled, which is the round-trip distance.

[5614]

As in it took 6 seconds for the signal to go to the object AND back to the bat.

 

So it took 3 seconds to reach the object, and then another 3 for the signal to come back to the bat.