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It takes 2.56s for the radio wave to return to the earth after it reaches the moon. It is known that the radio wave travels 3 * 10 quintic km per second, and the distance between the earth and the moon is calculated. (the result is accurate to 10000 bits)
Distance L = vs / 2 = 2.56x3 * 10 △ 2 = 3.84 * 10m
It takes 2.56s for the radio wave to reach the moon and return to the ground. The propagation speed of the radio wave is 3 × 108m / s. what is the distance between the moon and the ground?
The time of radio wave transmitting from the moon to the ground is t = 12 × 2.56s = 1.28s, so the distance between the moon and the ground is s = VT = 3 × 108m / s × 1.28s = 3.84 × 108m. A: the distance between the moon and the ground is 3.84 × 108m
The distance between the moon and the earth is 380000 km. If the moon is used as a microwave relay station, the radio waves emitted from the ground transmitting station will be transmitted
How long does it take to return to the ground receiving station
The speed of radio wave can be calculated according to the speed of light, namely 3 * 10 ^ 5 km / s
So the total distance is 38 * 10 ^ 4 * 2 km = 7.6 * 10 ^ 5 km
Time is (7.6 * 10 ^ 5) / (3 * 10 ^ 5) = 76 / 15 s, about 5 seconds
The distance between the earth and the moon is about 3.84 x 10 ^ 8m. The propagation speed of radio wave is about 3 x 10 ^ 8m / s,
How long does it take for radio waves from the earth to reach the moon
t=s/v=3.84x10^8m/(3x10^8m/s)=1.28s
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