Arthur
Arthur is my first friend in London, whom I met and formed a warm friendship with around running until age and injury prevented this shared pastime. Then, Arthur was the project engineer at TRW (now Northrop Grumman) overseeing a joint venture with O2 to provide a closed wireless network to Britain's police force and ensuring 99% availability (consumer mobile is way less). Arthur today remains my go-to pal on anything geeky, and we often discuss the abstract on a good British ramble which we used to do quite regularly pre-kids (our last walk several years ago started at Waterloo station at 8PM, ending well after midnight. More recently we biked to Oxford). Arthur bikes everywhere on his 20 year-old trusty ten speed (geer shifts on bike frame), and has spent the past three years re-wiring his penthouse near Regent's Park, NW1. Recently I asked Arthur to describe electricity for Eitan, and his response:
"Two parts to the answer
1) ENERGY
Energy is a thing that makes things HAPPEN, MOVE OR CHANGE. Examples: toaster, when you run, growing plants, driving a car, heating the kettle, burning a candle, even light from a light bulb is energy, light from the sun.
Every now and then, point out examples of energy in action as you go through the day
Main types: HEAT, MOTION, LIGHT, ELECTRICITY,
Energy is conserved: it moves around between objects and changes type, but it never disappears. Examples:
a. The toaster turns electricity into heat
b. When you run, you turn energy in your food into movement AND HEAT (which is why you feel hot when you exercise)
c. Growing plants take light from the sun and make it into plant stuff (and we get the energy back when we run and "burn off" the plants we ate the day before
d. Motion of car comes from energy in gasoline
e. The kettle makes heat out of electricity
f. Candle makes light and heat out of the energy in the wax (which came from the bees which ate plants which got the energy from the sun)
g. A light bulb makes heat and light from electricity
SO ELECTRICITY IS ENERGY - IT MAKES THINGS HAPPEN
Part 2 ELECTRONS
First, rub two balloons with a piece of wool cloth and show that the balloons repel each other. Explain that there are tiny things called electrons that repel (very similar to little magnets) and that we've just put electrons on the balloons from the wool cloth.
Wires are full of electrons. There's a power plant where they have machines that push on electrons and because the electrons push on each other, a push at the power station appears as a push on the end of the wires in your house (demonstrate pushing electrons by putting Sonnet, Madeleine and Eitan side by side (not front to back) in a line pushing pushing against each other's hands. Then you as the power plant push at one end of the line. Your push should propagate through the line and appear at the other end).
Show wires by examining the plug and cords going to all the electrical devices in the house (including lamps in the ceiling)
So electricity is just pushing electrons. So a push at the power station is a push in your house. All your appliances turn the push into some other kind of energy that is useful. Heat from a kettle, the turning of an electric drill (or if you don't have one, show the motor in the vacuum cleaner turning)
Eitan may not get it all on the first pass, but the concepts of energy and electrons are worth getting used to from early on
Phew!"