The Bucket Squirt Phys-elation

There are occasions when you can get hopped up on physics. You'll be taking it easy exploring a bit of physics when BAM! You find out about something revolutionary. Something like quantum tunnelling. It leaves you shocked and excited. Perhaps even sit-down excited. It's the physics feel good moment. A phys-elation. It's not the same as a eureka moment, but it is a good thing that happens more than once. Sometimes you'll know it's coming, sometimes you won't. But, they're pretty hard to forget.

Physics not drugs!

A Phys-elation Memory

Despite being hard to forget, I've never really reminisced about a phys-elation. Nonetheless, whilst writing The Seaside Physics Juxtaposition, a particular phys-elation memory crawled back to the surface of my mind. It was at A level, learning about circular motion. If you swing around a bucket of water fast enough, the constant change in velocity will force the water to stay in the bucket. However, if the bucket has a hole in bottom, water will squirt out of the hole... most of the time. If the holey bucket is being swung vertically, there is a point at the top  of the swing where the force of gravity can equal the centrifugal force that makes the water squirt out.

If you want to know the equation, the velocity for a squirt free climax has to be:

in which g is the acceleration due to gravity and r is the distance to the bucket from the pivot - your shoulder.

When the velocity is this value at the climax of the swing, water will stop squirting out. All standard stuff, no phys-elation at this point.

After learning this, we (the class) wanted proof, so we spent the rest of the lesson getting it. And we got it. This is our recording taken by a phone taped to a holey bucket of water being swung around.

It wasn't a eureka moment... but it was a phys-elation! You know what they say, small things please small minds, but not all minds pleased by small things are small minds... savvy?

The Circular Motion

If you want to look up any of the physics mentioned here, The Fitzpatrick Physics Files will direct you to a perfect resource for it. Specifically the Classical Mechanics notes.

That bit at the end...

The video above is courtesy of Skipper - it was his phone that recorded it. Skipper blogs over at Confessions of a Wildlife Biologist. You should check it out! Thanks to Skipper for risking his phone all those years ago!

Confessions of a Wildlife Biologist,