Gap Fill - A Zeptosecond - Level 2


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   decimal      equipment      ever      fast      molecule      scientists      shorter      something      tiny      trillionth  

Paragraph 1

Today, many things are getting . Scientists have just measured very short. They recorded the shortest unit of time measured - a zeptosecond. This is a tiny, fraction of one second - a of a billionth of a second. It is a point followed by 20 zeros and then a 1. The study atomic physics at the Goethe University. They used high-tech to measure how long it takes a photon to cross a hydrogen . The scientists said it took 247 zeptoseconds for this to happen. This is too for humans to sense or see.

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