183 Reducing Mileage

I spent slightly less than an hour of my life looking for old Readers' Digest issues to search for this article that I remembered from a few months back... and I took the liberty to rearrange the magazines back in chronological order, so yeah, I realised I'm a bit obsessive-compulsive when it comes to book arrangements. Must have picked up from the days spent in the library.
Anyway, back to the main point. The article I was looking for is titled "Easy Does It : Star of The Slow Lane", and it's about how to reduce your car mileage, i.e the amount of petrol the car guzzles up per kilometre. Yes, I'm trying to help you drivers out there to save petrol, in light of the recent crazy price increase. So, here's how Physics can save you some money:
  • Reduce the car's mass. It's rather obvious, isn't it? F = ma [F = force required by engine, m = mass of vehicle and contents, a = acceleration]. The more mass there is in the car, the more force is required to get going. So, throw out all that unnecessary add-ons, that TV, the unused third row of seats, sub-woofers, roof racks, junk in the trunk, and as I heard on the radio, those 300 useless one cent coins, and that nagging woman (implying: don't bring unnecessary passengers, no offence, ladies). But please, don't toss the safety belts.
  • Don't rev your engine. I don't know why people must do it at traffic lights, but just take note: revving your engine is a waste of petrol, wrecks your engine and irritates people like me. So, don't do it please, the few drops you have used would be able to get you to the next traffic light.
  • Don't "tekan" so hard. Just push gently on your pedal when you are at beginning to move or just completed a turn. There's no point accelerating that much, it's not going to do you any good, since you're going to have to stop again somewhere, unless, of course, you're in a big hurry. Even if you are, studies show that you only gain 75 seconds from a 30 minute journey doing this. So, why bother?
  • Use every bit of momentum that your car possesses while approaching a traffic light or a corner. The idea is this: take your foot of the gas pedal, and let the combination of momentum and friction take you to the junction, without having to step on the brake pedal. Braking is a waste of the kinetic energy that the engine has supplied you, so don't brake unnecessarily.
  • Drive smoothly, and don't go over the speed limit. Going at high speeds increase the amount of drag and friction the car experiences, and overcoming them is actually a waste of petrol... and when you're at high speeds, you're bound to have to brake rather hard, and yet another great waste of kinetic energy.
  • Use potential energy to your advantage, especially in a town like Seremban, where there are far too many hills. If you know you're approaching a downwards slope, let go of the gas pedal, and let the potential energy take you down, and when you reach the bottom of the hill, don't brake just yet, let it take you as far as it can, until the car is too slow.
  • If you're waiting for someone for more than 3 minutes, please turn off the engine. An idling engine is a parasite that eats up petrol without doing anything. But, since the Malaysian weather can be unforgiving, try winding down your windows if you're in a shady place or waiting in the later part of the evening. If it's really, really hot, just get out of the car, and find some place where you can wait more comfortably. Unless you're illegally parked, that is.
  • Check your tyres. Bare and/or under/overinflated tyres has less grip, and requires more force to start moving, stop or go round bends. It's simple circular motion Physics. Not to mention, it's dangerous too.
  • Wait in a queue on neutral. Don't put the car on "Drive", which will require you to step on the brake, implying that the engine is supplying thrust. If it is inching traffic (like in a traffic jam, or at a toll), put the car on"Drive" but don't step on the gas pedal, the car can move on its own, although a little slower.

It's really not that hard to follow all these rules. I tried it out last night, and it went quite well for me, with the added bonus that I felt happy that I'm doing my part for my family and the environment. It really is killing two birds with one stone. So, do try these practises for yourself, I trust that these really do work, since I trust the Physics and the logic of it all.