Physics help greatly appreciated!!!!!!!!!!!?

Question

An oceanic depth-sounding vessel surveys the ocean bottom with ultrasonic waves that travel 1530 m/s in seawater. How deep is the water directly below the vessel if the time delay of the echo to the ocean floor and back is 7 s?


answer in units of m

Answer 1

let t represent the time it takes the ultrasonic way to reach the bottom of the ocean. The tota total is 7s, then 7 - t is the time it takes the ultrasonic wave to travel back to the vessel


Distance = speed * time

going down:
d = 1530t

going up
d = 1530(7 - t)

1530t = 1530(7 - t)
1530t = 10,710 - 1530t
3060t = 10,710
t = 3.5s


d = 1530(3.5)
d = 5,355m

Answer 2

Hi,
s = vt (Where s = distance, v = velocity, t = time.)
=1530*7
=10710
Now, that is the distance to the bottom and back. So, of course, divide that by 2 to get the distance from the bottom of the vessel to the ocean floor.
s = 10710/2
5355

Hope this helps.
VE

Answer 3

if it takes 7s for the signal to be returned then it only takes 3.5s for the signal to reach the ocean bottom.

therefore 3.5s at 1530m/s..

= 5355m !