Grandpa Fenn's Workshop

The Chain Reaction Bench

Grandpa builds machines that do one small thing in a very big way. Today the small thing is ringing a bell.

Grandpa Fenn at the workshop door with his field notebook

Build it

Drop a marble. Place ramps, bouncers, fans, teeter boards, spinners and trampolines. Make the marble ring the bells. Drag a piece to move it. Tap a piece once more to turn it.

Grandpa Fenn

Grandpa is grinning. You built a real chain reaction.

Why it works

A marble at the top of the bench is holding energy. It got that energy when something lifted it up there.

Let go and the energy starts to move. It becomes speed. A ramp hands some of it along. A bouncer gives it a kick. A fan pushes on it.

At the end, the energy has gone into a sound. That is the ring of the bell.

Grandpa. Every machine I ever built is a way of passing energy from one thing to the next. Some of it always gets lost as a little heat. That is why the last bell rings softer.
Flicker the puppyFlicker keeps trying to catch the marble

Grandpa's notebook

A moving thing carries energy. A higher thing is holding it.

Each piece in the chain takes some and hands the rest along.

A good machine wastes very little on the way.

Big word for the day. Energy. It is what makes things move, heat up, light up and ring.

Grandpa has more machines on the bench.

Try the Lever Lab

Try the Pulley Lab

Try the Shadow Clock

Try the Water Clock

Try the Sound Maker

Try the Balance Scale

Try the Magnet Maze

Try the Windmill

Try the Wedge and the Screw

Try the Periscope

Try the Pendulum

Try the Kite

Try the Gear Train

Try the Lighthouse

Try the Siphon

Try the Hot-Air Balloon

Try the Telegraph

Try the Wheel and Axle

Try the Ramp Lab

See Grandpa's Invention Wall

Want a story first? Toby and Poppy have two.

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