试题与答案

(12分)太阳现正处于主序星演化阶段.它主要是由电子和、等原子核组成.维持太阳辐

题型:计算题

题目:

(12分)太阳现正处于主序星演化阶段.它主要是由电子和等原子核组成.维持太阳辐射的是它内部的核聚变反应,核反应方程是,放出的核能最后转化为辐射能(普朗克常量J·s).要求:

(1)已知质子质量mp,氦核的质量mα,电子质量me,光速c.求每发生一次上述聚变反应所释放的核能;

(2)用上述辐射中产生的波长为400nm某一单色光去照射逸出功为3.0×10-19J金属材料铯时,能否产生光电效应?若能,求出产生的光电子的最大初动能.

答案:

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