Shocking “news”

Apparently, Anna Nicole died of a drug overdose. No, really! It comes as a total shock to the millions of people who were deeply involved with her life (likely because they lacked one of their own.) And she was such a nice girl, too.

Blech.

There’s nothing that makes me turn off the TV faster these days than news about A.N. And I’m not sure what disgusts me more, that the news channels play the story as if it has any importance whatsoever, or that people actually watch it.

Step on it

In an effort to squeeze an extra couple of miles per gallon out of our new family-hauler, I’ve been accelerating very gently out of stops and trying to go easy on the brakes as I approach them. I had always been taught that the most efficient driving involves avoiding quick stops and starts.

So I got thinking about it from a physics approach and had to dust the cobwebs off my memories of 1D equations of motion and the definition of work and kinetic energy. It turns out that there shouldn’t be any difference at all between the fuel usage of the driver that punches the gas out of a dead stop and one who accelerates slowly from it. Since work (the energy that it takes to get the car moving to a certain speed) is simply the difference between the kinetic energy at rest (0) and the kinetic energy at final speed (1/2mv^2), the energy used is the same regardless of how fast the car gets to that speed.

On the flip side, it is definitely easier on the engine and brakes to avoid fast stops and starts, but mileage is more affected by the number of starts and stops. (Tailgating with frequent brake-tapping kills it too.)

The moral of the story is obviously that to save gas, one should avoid stopping. (Stop signs, red lights, brick walls, lakes….)