Earlier today I posed you these two problems about curious objects. Here they are again with solutions.
1. Pythagoras’ Cup
Pythagoras, the Greek mathematician and mystic, is credited with designing a cup with the following characteristics:
1) If you pour it up to a certain level, it behaves like a regular cup.
2) If you throw it beyond that level all the liquid empty into the cup through a hole at the bottom of the cup.
Can you draw the mechanism inside the cup?
The mechanism inside is very simple and has no moving parts. (If you’re a plumber, you might find this very easy.)
The cup is a cute metaphor for moderation in life. Fill it just a little too much and you’ll lose everything.
Solution
The cup has a central chamber that is filled from the base of the cup, as shown above. The chamber fills as normal until the liquid overflows, creating a siphon that will empty the lot thanks to gravity. Flush toilets and the fabric softener tray in a washing machine use the same trick.
2. Backward jalopy
Design a simple mechanism for a four-wheeled toy vehicle so that when you pull a piece of string backwards out of the vehicle, the vehicle moves forward.
Solution
You will need to add a pulley system, like the one in the video above. The rope is wound around an axle, which moves a belt connected to the wheel axle as it unwinds.
I hope you enjoyed today’s puzzles. I’ll be back in two weeks.
I’ve been doing a puzzle here on alternate Mondays since 2015. I’m always on the lookout for great puzzles. If you want to suggest one, email me.
