A single wingtip feather, he found, moved a fraction of an inch, gives a smooth sweeping curve at tremendous speed.
他发现,把翼消的一根羽毛转动那么一丝丝,就可以在高速下平平稳稳地来个急转弯。
2
It can take 6.1 million pictures in a single second, at a shutter speed of 440 trillionths of a second. Light itself moves just a fraction of a centimeter in that time.