Finding distance between two origin points; waves

AI Thread Summary
To find the distance from the boat horn to the submerged scuba diver, the speed of sound in water (1482 m/s) and the distance from the friend on dry land (22.0 m) are crucial. The diver hears the sound directly above, while the friend hears it from a distance, allowing for a triangulation of the distances involved. Using the known distances and the speed of sound, one can calculate the time it takes for the sound to travel to both individuals. This information helps in determining the total distance from the horn to the diver. The discussion emphasizes the importance of utilizing all available data to solve the problem effectively.
Butterlegs
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1. A submerged scuba diver hears the sound of a boat horn directly above her on the surface of the lake. At the same time, a friend on dry land 22.0 m from the boat also hears the horn (Figure 1). The horn is 1.2 m above the surface of the water. What is the distance (labelled by"?" in Figure 1) from the horn to the diver? The speed of sound in water vwater = 1482 m/s.

I have absolutely no idea where to start with this. I am completely stumped. Any help would be greatly appreciated
 
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So you know the speed of sound in water (and air, presumably) and you need to know the distance. What bit of information are you missing to convert a speed to a distance?
You should find that you can use the other given data (the friend at 22.0 m on dry land) to calculate this.
 
I really don't know how I missed that.
 
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