09-03-2013, 09:12 PM
I'm on my phone and don't feel like switching to the calculator but the answer is (9,000/1,500) seconds.
If you're curious why that works though, it is stated that sound can travel 1,500 meters in 1 second in water so to calculate how long it would take to travel 9,000 meters, you simply take that distance and divide it by the sound's speed. It ties into the dimensional analysis from the other day. In units, you have [distance]/([distance]/[time]). The two distances cancel out leaving you with just the time you're looking for (really, it leaves you with 1/(1/[time]) which simplifies to [time].
And since I typed all of that up, I realized that the answer didn't require a calculator. It's 6 seconds.
If you're curious why that works though, it is stated that sound can travel 1,500 meters in 1 second in water so to calculate how long it would take to travel 9,000 meters, you simply take that distance and divide it by the sound's speed. It ties into the dimensional analysis from the other day. In units, you have [distance]/([distance]/[time]). The two distances cancel out leaving you with just the time you're looking for (really, it leaves you with 1/(1/[time]) which simplifies to [time].
And since I typed all of that up, I realized that the answer didn't require a calculator. It's 6 seconds.