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一次流星雨能有多少人看到？

贫论员 2011-08-09 20:20:12 ( reads)

地球的半径为6400公里。流星在离地面50公里时由于跟大气摩擦开始燃烧发光所以我们能见到。一般在离地面40公里时就已经烧光了。

地面上能看到流星的地方有多大？

跟帖(15)

wxcfan123

2011-08-11 17:43:39

不会是要死算那球冠的表面积吧？

jinjing

2011-08-12 09:39:17

about 4%.?

wxcfan123

2011-08-13 12:05:27

回复：一次流星雨能有多少人看到？

jinjing

2011-08-13 14:27:31

r/2(R+r)=about 4%o.Please note the tangent line.

贫论员

2011-08-15 12:07:10

0.4%?

jinjing

2011-08-15 16:33:51

Yes.Only estimat,we don't know the time,it has relation with the

jinjing

2011-08-15 16:50:46

It has relation with the rotation of the Earth.

jinjing

2011-08-13 14:31:26

sorry, youare right.

贫论员

2011-08-15 11:42:51

结果这么clean啊！怎么推倒出来的？

贫论员

2011-08-15 12:09:26

哦，原始推导居然用了曲面积分。

jinjing

2011-08-15 16:26:28

不是曲面积分。是积分求旋转面.

wxcfan123

2011-08-15 14:39:14

死算出来的。一直没想出纯几何方法求h

jinjing

2011-08-15 16:44:33

You Rit. We also can use similar tringles and ...getting h(r-h)=

jinjing

2011-08-15 17:31:02

(R+r-h)^2=(R+r)^2-R^2-h^2,...

jinjing

2011-08-15 17:33:49

Sorry, It should be: (R+r-h)h=(R+r)^2-R^2-h^2,...