Water Clock

As part of our study on Ancient Egypt, we made a water clock. There are several "how to's" on the web, but we decided to use a make-shift version of this one.

Items we used

2 yogurt containers
Clear Duck tape
thumb tack
permanent marker
ruler
water
stopwatch
food coloring (optional)

I taped two large yogurt containers together and then made tic marks at every inch inside the top cup with a black Sharpie marker. I used a thumb tack to punch a single hole in the bottom of the top cup as well.

We found that it was easier to watch the water level with a little food coloring in it as well.



I had Will make an estimate of how long it would take to get from the first mark to the second one (1 inch apart) and then compared it to the actual time. Then I placed a 1/2 inch mark in between and had him estimate how long he thought that would take. We then compared it to the actual time.

Then I punched a second hole in the bottom of the top cup and had him estimate the time between the inch marks based on his previous results. Then we did it again for the 1/2 inch mark with the two holes.

We calculated how long it would take to empty the top bucket with two holes in it, knowing that it is 5 inches deep. Lastly, we calculated how many times we would have to fill our container to reach one hour's worth of time.

This was a fun, easy experiment!