Posted by **Elisa** on Monday, August 4, 2008 at 10:55pm.

Please help. I got 338.82 for the velocity and wanted to get the distance, but I can't seem to do it because I don't have the wavelength. Please help!

A stone is dropped from rest into a well. The sound of the splash is heard exactly 2.20 s later. Find the depth of the well if the air temperature is 12.0°C.

- Physics -
**DrBob222**, Monday, August 4, 2008 at 10:59pm
Here is a site that allows one to calculate the speed of sound in air at the desired temperature.

- Physics -
**Elisa**, Monday, August 4, 2008 at 11:06pm
That is the correct speed, but I don't know how to find the depth of the well, which is what the question is asking for.

- Physics -
**DrBob222**, Monday, August 4, 2008 at 11:14pm
Here is a site that allows one to calculate the speed of sound in air at the desired temperature.http://www.sengpielaudio.com/calculator-speedsound.htm

Isn't distance = rate x time.

So multiply the speed of sound x 2.2 seconds = ??

- Physics -
**Elisa**, Monday, August 4, 2008 at 11:20pm
Nope that doesn't give the right answer, but thanks lots for your help!

- Physics -
**DrBob222**, Monday, August 4, 2008 at 11:24pm
Make sure you have the right units. Do you know the answer? If speed is in meters/second then the distance will come out in meters.

- Physics -
**Count Iblis**, Tuesday, August 5, 2008 at 11:35am
I think you should take into account the time it takes for the stone to hit the water. If the distance is d, then the time needed for the stone to reach the water, t1, follows from:

1/2 g t1^2 = d ------->

t1 = sqrt(2 d/g)

The time needed for the sound to reach you is:

t2 = d/v

where v = 338.82 m/s is the speed of sound.

So, the total time is:

T = t1 + t2 = d/v + sqrt(2 d/g)

It is given that T = 2.20 s, so we get the equation:

d/v + sqrt(2 d/g) = 2.20 s

You can put d = x^2 to convert this to a quadratic equation. I find

d = 157.7 m (but I haven't double checked...)

## Answer This Question

## Related Questions

- physics - A stone A is dropped from rest down a well, and in 1 s another stone B...
- Grade 11 Physics - A stone is dropped from rest from a bridge that is 45 m above...
- Physics - A stone is dropped off the science building and accelerates, from rest...
- physics - A stone is dropped off the science building and accelerates, from rest...
- Physics(Please help) - 1) A cave explorer drops a stone from rest into a hole. ...
- Physics: Non uniform motion - I have not done much physics before: I don't get ...
- Physics(Please respond) - 1) A cave explorer drops a stone from rest into a hole...
- science - A stone is dropped into a river from a bridge 43.9 m above the water...
- Physics - a stone is dropped from a 75m building. when a stone has dropped 15m, ...
- physics - A spelunker drops a stone from rest into a hole. The speed of sound is...

More Related Questions