英语翻译For example:the photoelectric effect.this was a puzzle i

For example:the photoelectric effect.this was a puzzle in the early 1900s.when light hits a metal,like zinc,electrons fly off.this can happen only if light comes in little packets concentrated enough energy to knock an election loose.A spread-out wave wouldn't do the photoelectric trick.
例如:光电效应,在1900的早期这还是个难题, 当光照在金属上,列如锌、将激发出电子.这种现象只可以发生在以下条件： 当入射光以微小颗粒并集中足够的能量来将电子激发.一个分布的光波不不能解释光电效应.
注：这里是在解释光的“波粒二相性”,指出光的粒子性是不能用光波的传播理论来解释的.