By creating an account, you acknowledge that PBS may share your information with our member stations and our respective service providers, and that you have read and understand the Privacy Policy and Terms of Use.
You have the maximum of 100 videos in My List.
We can remove the first video in the list to add this one.
Season 5 Episode 2 | 5m 54s
| Video has closed captioning.
How did we come up with our system of telling time? Why do we divide the day into 24 hours of 60 minutes each, and put 60 seconds in each minute? Where does the definition of a second come from? And who decides what clock shows the correct time? There’s clearly a lot of questions when it comes to time.
