The number of man-made objects in Earth orbit has been growing each year.

VOA: special.2009.04.01

n So the velocity is given by this product of the quantum number n Planck constant 2 pi mass of the electron time the radius of the orbit, which itself is a function of n.

速度是量子数,普朗克常数2π乘以轨道半径的值,它自身也是n的函数。

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