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The distance between the moon and the earth is about 3.8 × 15 km. So the distance of the moon around the earth in half a lunar month is________ The magnitude of displacement is_____ km. How to do ah... Understand please make a complete analysis I will be very grateful to you
A common sense: the moon around the earth is a lunar month. In half a lunar month, the trajectory of the moon is half a circle
The distance is the length of the track, that is, the semicircle length = 3.14 * 3.8 * 10 ^ 5 = 1.19 * 10 ^ 6 km
Write down the position of the moon at a certain time, and write down the position of the moon half a month later. The linear distance between the two positions is the displacement of the moon, displacement = diameter = 2 * 3.8 * 10 ^ 5 = 7.6 * 10 ^ 5 km
The speed of radio wave is about 300000 kilometers per second. It takes 2.56 seconds to send radio wave from the earth to the moon and reflect it back to the earth. If a rocket is launched from the earth, the average speed of the rocket is 11.2 kilometers per second. How long does it take for the rocket to reach the moon
Earth Moon distance = 300000 * 2.56/2 = 384000 (km)
Time = 384000 / 11.2 = 34285.7 seconds
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