※ 引述《nonoman (nono)》之銘言： : [領域] 大學普物 (題目相關領域) : [來源] University Physics 12e Hugh D. Young : Chapter8 的第108習題 : [題目] : When two hydrogen atoms of mass m combine to form a diatomic hydrogen : molecule(H2), the potential energy of the system after they combine is -△, : where △ is a positive quanity called the binding energy of the molecule. : (a) Show that in a collision that involves only two hydrogen atoms, it is : impossible to form an H2 molecule because momentum and energy cannot : simultaneously be conserved. : (hint: if you can show this to be true in one frame of reference, then it is : true in all frames of reference. Can you see why?) 在兩顆氫原子的質心坐標，形成氫分子動能守恒最後動量必需是零。可以發現這樣不可能能量守恒。 : (b) An H2 molecule can be formed in a collision that involes three hydrogen : atoms. Suppose that before such a collision, each of the three atomes has : speed 1.00*10^3 m/s , and they are approaching at 120° angles so that at : any instant, the atoms lie at the corners of an equilateral triangle. Find : the speeds of the H2 molecule and of the single hydrogen atom that remains : after the collision. The binding energy of H2 is △=7.23*10^-19 J, and the : mass of the hydrogen atom is 1.67*10^-27 kg. 這個就跟平常守恒問題做法一樣。 -- pub 2048R/9CB5B35A 2/20/2006 Matthew Zhang (gmail key) <[email protected]> Primary key fingerprint: 9607 7903 1D12 F060 AD76 3705 5CE2 0A3E 9CB5 B35A --

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