Monday, October 5, 2015

Bikes & Gears

Serena has caught the bike fever. It started when she rode a high-end speedy racing bike at the triathlon this summer. Now she & Daddy go on long bike rides on nice weekends. Curiously their excursions always end up at a place that sells ice-cream or milkshakes or hot chocolate...

While they're out spinning around, I sit and contemplate how to weave this new interest into our homeschool days.

Gears! Physical science unit, checked.

We watched a few intro videos like Gear Basics and How Do Bike Gears Work. We love the Smarter Every Day video called The Backwards Brain Bicycle - so cool how our brains get hardwired! Some excellent books on the subject include Pedal It! and Go Fly A Bike!.

The best part about science though is always the hands on stuff. There's no shortage of bikes in this home for show & tell! Serena gets to tinker with bike mechanic Daddy.

We borrowed a set of K'Nex with instructions to build a cool little stationary bike. It showed us a simplified version of a sprocket gear system, but it didn't really illustrate the power of gear ratio as the front & back gears are of the same size.

This crank fan, however, did the trick marvellously. We started with 2 identical gears in the fan's spur gear system, then switched to using one big and one small gears. The speed of the fan is significantly different depending on whether we use the big gear to drive the small one or vice versa.

Next K'Nex model to build is a blender that uses a crown gear system. Fun!

"Life is like riding a bicycle: you don't fall off unless you stop pedaling." Claude Pepper

"Life is like a 10-speed bicycle. Most of us have gears we never use." Charles Schultz

Better keep pedaling and use those gears!

1 comment:

  1. We love the explanation of the gearing system .Great work.
    Like the idea of a destination ride to an ice cream stop.
    Great work. Love Nanny & Papa