更新1:
also can anyone tell me the age of the moon?
更新2:
sorry to keep badgering you guys, but i dont suppose anyone knows the density of the Van Allen radiation belts?! thanks for all your answers btw, they've really helped.
what is the mass of the moon?
2009-03-08 2:15 pm
i dont want anyone to say 7.35e22, because i have no idea what that means. if you give that can you please explain what it means, or convert it into a normal number, and give the measurement thing(eg. kg)
回答 (5)
2009-03-08 2:23 pm
✔ 最佳答案
This much: < ------------------- > (not to scale).Heh, ok, serious now. Type "mass of moon" into Google, and it tells you precisely :)
7.36 * 10 ^ 22 kg.
That means 73,600,000,000,000,000,000,000kg.
The "e22" or the * 10 ^22 bits mean the same thing: take the number preceding them, and multiply by 10 to the power of 22. The reason it is used is because they're bloomin' big numbers!
Google link for your viewing pleasure.
2009-03-08 2:40 pm
The rocks brought back from the Moon appear to be 4.5 billion years old (same age as Earth's rocks seem to be), so that matches the "impact theory" about the formation of the Moon.
Such an impact would have completely melted the crust, so that resets the clocks (Earth's and Moon's) to zero.
It would have occurred when the planetary system was still very young so that our real, total age is not much more than what we can measure with the oldest rocks.
---
The Mass of Moon is 0.0123 times that of Earth. Or, doing the inverse: take the mass of Earth and divide it by 81.3
This information is actually useful in that you do not always need the exact mass (in kg) to do many calculations. For example, if you want to find the barycentre (centre of mass») of the Earth-Moon system, then you figure:
The total mass is 81.3 + 1 (Earth + Moon) = 82.3
The barycentre is 1/82.3 of the way between the centres.
On average: 384,400 km.
Therefore, the barycentre is:
384,400 / 82.3 = 4,670 km from Earth's centre (still well inside Earth's surface).
Had it been outside Earth, we could then talk of a "double planet".
---
7.35e22 is short hand for
7.35 x 10^22 kg
10^22 is shorthand for "10 raised to the power 22" which happens to be a 1 followed by 22 zeros (it works that way because we use numbers in "base-10").
7.35 x 10,000,000,000,000,000,000,000 =
73 500 000 000 000 000 000 000 kg
Such an impact would have completely melted the crust, so that resets the clocks (Earth's and Moon's) to zero.
It would have occurred when the planetary system was still very young so that our real, total age is not much more than what we can measure with the oldest rocks.
---
The Mass of Moon is 0.0123 times that of Earth. Or, doing the inverse: take the mass of Earth and divide it by 81.3
This information is actually useful in that you do not always need the exact mass (in kg) to do many calculations. For example, if you want to find the barycentre (centre of mass») of the Earth-Moon system, then you figure:
The total mass is 81.3 + 1 (Earth + Moon) = 82.3
The barycentre is 1/82.3 of the way between the centres.
On average: 384,400 km.
Therefore, the barycentre is:
384,400 / 82.3 = 4,670 km from Earth's centre (still well inside Earth's surface).
Had it been outside Earth, we could then talk of a "double planet".
---
7.35e22 is short hand for
7.35 x 10^22 kg
10^22 is shorthand for "10 raised to the power 22" which happens to be a 1 followed by 22 zeros (it works that way because we use numbers in "base-10").
7.35 x 10,000,000,000,000,000,000,000 =
73 500 000 000 000 000 000 000 kg
2009-03-08 2:47 pm
The mass of the moon is about 73,500,000,000,000,000,000,000 kg
or
seventy three sextillion five thousand quintillion kilograms.
How's that for a large number? ;-)
or
seventy three sextillion five thousand quintillion kilograms.
How's that for a large number? ;-)
2009-03-08 2:26 pm
I just remember .0123 time the Earth mass, which is to a very good approximation 6 * 10^24 kg.
e22 is short for 10^22
e22 is short for 10^22
2009-03-08 2:24 pm
Mass of the moon =7.347 7 × 1022 kg (0.012 3 Earths)
收錄日期: 2021-04-20 21:57:05
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