英语翻译Whatmakesitrain?RainfallsfromcloudsforthesamereasonasanythingfallstotheEarth.TheEarth'sgravitypullsit.Buteverycloudismadeofwaterdroplets(微滴)oricecrystals(结晶).Whydoesn'trainorsnowfallcontinuously

Question

英语翻译
What makes it rain?Rain falls from clouds for the same reason as anything falls to the Earth.The Earth's gravity pulls it.But every cloud is made of water droplets(微滴) or ice crystals(结晶).Why doesn't rain or snow fall continuously from all clouds?The droplets or ice crystals in clouds are very small.The effect of gravity on them is tiny.
Droplets and ice crystals act somewhat like dust in the air which is made visible(可见的) in the rays of sunlight.To the careless observer,dust seems to act in a totally disorderly(混乱的) way moving about freely without fixed direction.But in fact dust particles are much larger than water droplets and they finally fall.
The cloud droplet of ordinary size is only 1/2500 inch in diameter(直径).It is so small that it would take sixteen hours to fall half a mile in perfectly still air,and it does not fall out of moving air at all.Only when the droplet grows to a diameter of 1/125 inch or larger can it fall from the cloud.The ordinary raindrop has a million times as much water as a tiny cloud droplet.The growth of a cloud droplet to a size large enough to fall out is the cause of rain.

Answer 1

雨是怎么形成的?雨是从云里降下来的,犹如万物掉在地上一样,都是地球引力的作用.所有的云都是由微小的雨滴和冰晶构成的.为什么不能从云里持续的降雨或者雪呢?那是因为云里的雨滴或者冰晶太小了.地球引力的作用微乎其微.
微小雨滴和冰晶的运动方式有点像光柱里的尘埃一样.粗略地看,尘埃似乎都遵循一种无定向的运动方式.但实际上,尘埃粒子比微小雨滴大得多,这些粒子最终会因重力作用落下来.
云里的雨滴一般直径只有1/2500英尺.在绝对静止的空气中,如此小的雨滴每6小时才下降半英里,而且它们在运动的空气中不会落下.只有当雨滴的直径累积到1/125英尺或者更大,它们才能从云里降下.普通雨滴是微小雨滴的一百万倍大,雨的成因就是这些微小雨滴成长为足够大小的雨滴的过程.