A sonar pulse is sent to the ocean bottom at 25°C, and it takes 1.20 s for the echo to come back. How deep is the bottom?

0.90 km , 0.92 km , 1.79 km, or 1.84 km ?

Question

A sonar pulse is sent to the ocean bottom at 25°C, and it takes 1.20 s for the echo to come back. How deep is the bottom? 

0.90 km , 0.92 km , 1.79 km, or 1.84 km ?

michele_laino · Answer

we have to know how much is the speed of sound inside a sea water

michele_laino · Answer

I found that value in my textbook:
it is 1,460 m/sec

anonymous · Answer

oh oops sorry i am drawing the table now :P |dw:1433187822896:dw|

michele_laino · Answer

ok! ten we can pick 1,533 m/sec

anonymous · Answer

:)

michele_laino · Answer

so we can write:
$$\Large  1.2 = \frac{{2d}}{{1533}}$$
where d is the requested deepness, there the factro 2, is to take account that we are dealing with the echo

michele_laino · Answer

factor*

anonymous · Answer

ok! and then we get this?

1839.6=2d
d=919.8 ?

michele_laino · Answer

yes!

michele_laino · Answer

d=919.8 meters= 0.92 Km (approximated value)

anonymous · Answer

yay!! thank you!!:D