Distance from Flash: Soldier 20°C, 6 secs After Cannon Fire

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To determine the distance from the flash of a cannon to the soldier, the speed of sound at 20°C is 342 m/s. Given that the soldier hears the sound 6 seconds after seeing the flash, the calculation for distance is D = 342 m/s * 6 s. This results in a distance of 2052 meters. The discussion notes that the speed of light is negligible in this context, as it reaches the soldier almost instantaneously. The focus remains on using the speed of sound for accurate distance measurement.
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1. A soldier hears the sound of the firing of a distant cannon 6.00 seconds after seeing the flash. If the temperature is 20 degrees Celsius, how far is the soldier from the flash?



2. D = R * T



3. Since the speed of sound at 0 degrees Celsius is 330 m/s, the speed of sound at 20 degrees Celsius is 342 m/s.
With that being said, how do you find the distance? D = 342 * 6 ?
 
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Can anyone give me some insight?
 
Why are you unsure of your approach?
 
The only thing that could make this hard is if you wanted to take light into account. It takes some time for light to reach the soldier first, but its almost instant and makes no significant difference
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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