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km
Dec 2, 2009, 01:54 AM
Initial velocity of zero to a stone has been left to a well.moved down 4.7 seconds after falling tone is heard.sound speed 340m / s is, according to the level of the water wells at the beginning of the vertical distance to find?

km
Dec 2, 2009, 01:55 AM
Initial velocity of zero to a stone has been left to a well.moved down 4.7 seconds after falling tone is heard.sound speed 340m / s is, according to the level of the water wells at the beginning of the vertical distance to find?

Unknown008
Dec 2, 2009, 06:27 AM
Seems that you're using a bad online translator...

1. The time taken for the stone to fall from the mouth of the well to the water inside is given by:

s = ut + \frac12 at^2

Where s = distance
u = initial speed
t = time
a = acceleration due to gravity

2. The time for the sound to reach your ears is given by:

s = ut_o

where t_o is the time that the sound takes.

3. Since the distances are the same, equate the two equations. Also, you know that t + t_o = 4.7

That makes a quadratic equation. Solve for t and replace in one of your initial formulae to obtain the value of s, the distance.