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starji
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how deep is the well? (using speed of sound)
A boy drops a penny into a deep well. if he hears the splash 5.0 seconds after he releases the penny, how deep is the well? (assume the well is 20degrees C) (also assume there is no air resistance)
speed of sound: v=331+0.59T and basic kinematics
i've found the speed of sound to be 342.8m/s
if t=d/v then the time it takes the sound of the splash to reach the boy's ears is t=d/342.8
the time it takes for the penny to drop into the well is: d=vit+0.5at^2; the vi is 0 so d=4.9t^2 therefore the time it take the penny to drop is t=sqrt(d/4.9)
so from here i should be able to find the distance by 5=d/342.8+ sqrt(d/4.9), but it isn't working and I am getting tiny numbers
Homework Statement
A boy drops a penny into a deep well. if he hears the splash 5.0 seconds after he releases the penny, how deep is the well? (assume the well is 20degrees C) (also assume there is no air resistance)
Homework Equations
speed of sound: v=331+0.59T and basic kinematics
The Attempt at a Solution
i've found the speed of sound to be 342.8m/s
if t=d/v then the time it takes the sound of the splash to reach the boy's ears is t=d/342.8
the time it takes for the penny to drop into the well is: d=vit+0.5at^2; the vi is 0 so d=4.9t^2 therefore the time it take the penny to drop is t=sqrt(d/4.9)
so from here i should be able to find the distance by 5=d/342.8+ sqrt(d/4.9), but it isn't working and I am getting tiny numbers
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