Getting traction in learning

I watched a documentary on YouTube about the development of the Shinkansen, the Japanese Bullet train. The engineers faced a number of challenges in trying to get trains to travel faster. Chief among them was traction. Steel wheels moving on steel rails are clearly not going to provide as much traction as rubber on asphalt. The problem is compounded if you have super-powerful electric locomotives trying to put down more than ten thousand horses across a contact patch that is no more than a few square centimeters on each wheel. What you get is wheel spin, the phenomenon you witness when you watch a drag racer spin its rear tyres at the starting line, effectively converting a lot of rubber into a lot of smoke.

One way to solve the problem is to increase weight on the driven wheels, but this can be counterproductive to payload, the stuff that people are paying you to haul. The other method, known to automobile users for some time, is what the Shinkansen engineers adopted: All-Wheel-Drive.

Just as a 4x4 moves off the line a lot more efficiently, in terms of traction, than a front wheel drive, the Shinkansen employs multiple drive units, electric motors at almost all the wheels to get the train moving along quickly. This increased traction aids rapid acceleration, especially important if you are planning on stopping every few kilometers and yet hoping to achieve average speeds in excess of 160 kmph. Incidentally, these EMUs or Electric Multiple Units are not unique to the Shinkansen. Most urban metro systems, where rapid acceleration after multiple stops is important, use EMUs. Most long distance trains, on the other hand deploy a locomotive at the front end to haul the free-wheeling carriages along. The bullet shaped ends of the Shinkansen trains, then, are not locomotives at all, but control cabins with a nose for aerodynamic efficiency to reduce air resistance.

Allow me a metaphor to connect this discussion to the topic of today's blog-post. Teachers are like train systems; some prefer the lecture method, where the professors do all the work, like the locomotive trying to haul the freewheeling carriages along. The best ones are like the Shinkansen, facilitating learning through ensuring engagement, where the carriages pull their own weight. These best ones see their job as only removing the resistance to learning. You know which system accelerates faster.