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 ?

Answer 1

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

Answer 2

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

Answer 3

oh oops sorry i am drawing the table now :P

Answer 4

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

Answer 5

:)

Answer 6

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

Answer 7

factor*

Answer 8

ok! and then we get this?

1839.6=2d
d=919.8 ?

Answer 9

yes!

Answer 10

d=919.8 meters= 0.92 Km (approximated value)

Answer 11

yay!! thank you!!:D