Gap Fill - A Zeptosecond - Level 1


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   fast      photon      point      scientists      second      shortest      special      things      this      tiny  

Paragraph 1

Today, are getting shorter. Scientists just measured the unit of time ever recorded. It is a zeptosecond. This is - a trillionth of a billionth of a . It is a decimal followed by 20 zeros and then a 1. The study atomic physics. They used tools to measure how long it takes a to cross a hydrogen molecule. The scientists said it took 247 zeptoseconds for to happen. This is too for humans to see.

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