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needhelpperson
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The speed of light is 3.0*10^8 m/s and the speed of sound is 340 m/s. Find the vaule of the interger n in the following statement:"If you start counting seconds when you see something happen and stop when you hear it happen, for every n seconds counted the event was about 1 km away."
but 3 is not the exact answer is it?
I'll show my calculation.
time take light to travel 1000 m is 1000/(3 *10^8) = a
Sound traveled a distance during that time 340 * a = 1/750 m
So sound should reach there when:
(1000-(1/750)/340 = 749 999/255000 s
so each n = 749 999/255000s for each km
shouldn't the integer be 749999 which happen at 255 km , unless 749999 is not prime...
Leong said:[tex]\Delta t=t_{stop}-t_{start}[/tex]
[tex]\Delta t=s[\frac{1}{v_{sound}}-\frac{1}{v_{light}}][/tex]
For s = 1 km,
[tex]\Delta t=2.9s=3s[/tex]
n=3 s
but 3 is not the exact answer is it?
I'll show my calculation.
time take light to travel 1000 m is 1000/(3 *10^8) = a
Sound traveled a distance during that time 340 * a = 1/750 m
So sound should reach there when:
(1000-(1/750)/340 = 749 999/255000 s
so each n = 749 999/255000s for each km
shouldn't the integer be 749999 which happen at 255 km , unless 749999 is not prime...