Ship and Iceberg - Speed of sound question

[fchen720]

Homework Statement

17.While cruising the North Atlantic in a fog, a ship blew its horn, and received an echo from an iceberg 4.0 s later. The temperature of the air was 5°C, the temperature of the iceberg was 0°C, and the temperature of the water was 2°C In order to calculate the distance from the ship to the iceberg, the captain must also know the speed of sound in:

A.
ice at 0°C.
B.
water at 2°C.
C.
water at 0°C.
D.
air at 0°C.
E.
air at 5°C.

Homework Equations

n/a

The Attempt at a Solution

If there were no fog the answer would definitely be E, but since there is a significant
amount of water in the air I thought the answer was B.

Turns out the water doesn't make a difference because the answer sheet says E.
Could somebody please explain?

 

[Andrew Mason]

If there were no fog the answer would definitely be E, but since there is a significant
amount of water in the air I thought the answer was B.

Turns out the water doesn't make a difference because the answer sheet says E.
Could somebody please explain?

Water content has some effect on the speed of sound in air so to be perfectly accurate you should have the speed of sound in saturated air at 5° C. But I expect it is not much different than the speed of sound in dry air at the same temperature.

AM

 

[Astronuc]

Homework Statement

17.While cruising the North Atlantic in a fog, a ship blew its horn, and received an echo from an iceberg 4.0 s later. The temperature of the air was 5°C, the temperature of the iceberg was 0°C, and the temperature of the water was 2°C In order to calculate the distance from the ship to the iceberg, the captain must also know the speed of sound in:

A.
ice at 0°C.
B.
water at 2°C.
C.
water at 0°C.
D.
air at 0°C.
E.
air at 5°C.

Homework Equations

n/a

The Attempt at a Solution

If there were no fog the answer would definitely be E, but since there is a significant
amount of water in the air I thought the answer was B.

Turns out the water doesn't make a difference because the answer sheet says E.
Could somebody please explain?

The sound is traveling through what medium? What is the temperature of that medium?

 

[DaveC426913]

While foggy air certainly contains more water than dry air, I think you'll agree it doesn't have anywhere close to as much water in it as the sea.

 

[fchen720]

Thanks to everyone who answered.