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When is the moon closest to the earth Who knows
About 4.5 billion years ago, when the earth and the moon were the same planet
How long does it take for an astronaut on the moon to send a radio signal (traveling at the speed of light) to the earth
The average distance between the moon and the earth is 384 400 km
Light speed c = 299792.5km/s
So t = s / C = 384400 / 299792.5 = 1.28222 (s)
The speed of light is about 3x10 & # 179; km / s. It takes 10 years for the light emitted by a star to reach the earth. How many km is the distance from the star to the earth if it is calculated with the power of 3.1x10 in a year?
The speed of light is about 3x10 km / s
The speed of light should be 3x105km / s, s = VT = 3x105km / sx3.1x107s = 9.3x1012km
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- 3. There is a comet in the solar system that returns to the earth once in 76 years. What comet is it?
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- 12. The mass of the earth is 81 times that of the moon, and spaceships fly from the earth to the moon The distance between the moon and the earth is 3.84 times 10 to the eighth square meter. It is known that the mass of the earth is about 81 times that of the moon. The spacecraft is attracted by the gravity of the earth and the moon on the way to the moon. When it arrives at a certain area, the resultant force of gravity is equal to zero. How far is this area from the earth
- 13. How long does it take to get to the moon from the earth
- 14. If a man is in a spaceship flying at the speed of light, flying at the speed of light,
- 15. How to understand that a year spent in a spaceship traveling at the speed of light is equivalent to a million years on earth? For example, there should be no reference to time, it is absolute. For example, my watch in the spaceship will walk slower, the same watch, the pointer speed is the same, how can it be placed on the spaceship to walk one circle time, the earth will walk ten circles
- 16. Why does it slow down near the speed of light
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- 18. How long did it take me to fly from the earth at the speed of light to return to the earth at the same time, Is the time around him almost stagnant? Does it not mean that the faster the relative object is, the slower the time passes? How many years have passed on the earth? If it is 2 years, what is the difference between my time and that on the earth?
- 19. What's the fastest speed of American spaceship? When can Chinese spaceship reach the speed of light?
- 20. How many kilometers is the distance between the sun and the earth? How long does it take for sunlight to reach the earth? Don't be long,