Per second per second.

每秒钟，每秒钟。

youdao

Special relativity is also based on a second assumption that gives the speed of light - 186, 000 miles per second (300 million meters per second) - in a vacuum a special status.

狭义相对论也奠基于它的第二个假设：他所设定的真空中光速为每秒186,000英里(每秒300,000千米)有它的特殊地位。

youdao

Angular velocity means not how many meters per second but how many radians per second.

角速度不是指每秒经过的路程，而是指每秒经过的弧度。

youdao

thirty-six feet per second up. Very smooth, very quiet ride."

VOA: special.2009.07.15

And then we have c, the speed of light, 2.998 times 10 to the 8 meters per second.

然后我们知道光速等于，2，998乘以10的8次方米每秒。

麻省理工公开课 - 化学原理课程节选

So, if something cycles through five wavelengths in a single second, we would just say that the frequency of that wave is five per second.

如果一个东西在一秒,内经历了五个波长，我们就说这个波的,频率是每秒5次。

麻省理工公开课 - 化学原理课程节选

It galloped toward the planet's core, accelerating at gravity's constant 32 feet per second per second.

NPR: Defying Gravity, and Odds, in New Orleans

Bluetooth transmits data far more slowly than Wi-Fi, about 720 kilobits per second versus 11 megabits per second.

FORBES: FedEx Bites Into Bluetooth

Several digital cameras and camcorders today feature "slow-mo" modes of 240 frames per second or even 600 frames per second.

ENGADGET: Switched On: Photography is dead, long live photos