Tank position problem based upon sound of fire

AI Thread Summary
The discussion revolves around calculating the speed of a tank based on the time delay between the muzzle flash and the sound of gunfire. The speed of sound is determined to be 392 meters per second at 100 degrees Celsius. The first shot's sound reaches the observer 3 seconds after firing, while the second shot's sound reaches them 2 seconds later, indicating a 1-second difference in sound travel time over 10 seconds. This suggests the tank is moving at one-tenth the speed of sound. A correction to the temperature is advised, as 100 degrees Celsius is excessively high for typical conditions.
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Homework Statement



An approaching tank fires at you and you hear the sound 3 seconds after the muzzle flash. Ten seconds later the same tank fires again and you hear the sound 2 seconds after the flash. The temperature is 100 degrees Celsius. How fast is the tank going? How long until he reaches you.

Homework Equations



v=331.4 + .606Tc that is the speed of sound in air based upon the temperature.
v= wavelength symbol X frequency
These are the only ones i think that could help me but i could be mistaken.

The Attempt at a Solution



So i know the speed of sound in air is 392 meters/sec based upon the equation v=331.4 + .606Tc

v= 331.4 + .606(100)
v= 331.4 + 60.6
v= 392 m/s

I can't figure out where to go from here. to get the other answers thank you for any help
 
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Welcome to PF.

First of all you might want to check the ambient temperature of the terrain, because 100° C is a prodigious life stopping temperature. 100° F maybe?

In any event ...

At the first shot the speed of the bullet lagged the firing by 3 seconds. In 10 seconds later it lagged by 2.

So ...

In 10 seconds the tank covered the distance that sound covered in 3 - 2 = 1 seconds. The rank is traveling then at 1/10 the speed of sound.

Resolve the temperature and you should be on the sunny side of the street.
 
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