physics master. help me..?

Question by Castiqz: physics master. help me..?
i have a few questions regarding to physics
1. Very short wavelength of radio waves can be used to determine the distance of moon to earth and vice versa by measuring the time taken by the radio waves . Calculate the time delay when moon’s distance to the earth is 3.9 x 10^8 m.
2. What are the 2 distances of the moon in reference to the earth?
3. What causes earthquakes? What kind of waves that is generated by earthquake and the intensity & magnitude of the earthquake?

anyway, masters, thank a lot!!

Best answer:

Answer by CHRIS Q
So the radio waves have to go there and back, so our distance is 7.8 * 10^8 metres.

Time = Distance / Speed
Time = 7.8 * 10^8 / 3 * 10^8 = 2.6 seconds

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