Recent content by nolaman

1. You are correct that this is particular to motorcycles. Most motorcycles have a reduction chain and sprocket or gearset between the crankshaft and the transmission input shaft. There is also a reduction in the rear wheel drive between the transmission output shaft and the rear wheel. Cars...

So I figured out where the error was coming from (sloppy mistake), so the formula does work. Sadly, it contains the conversion from power back to force. I hadn't noticed it until I started looking for the source of the error. With power in this case defined as (torque * (rev/sec) * 2 *...

With the given information you can calculate engine horsepower, which is the same a rear wheel horsepower. You can also calculate speed. However, every time I try this there is an error of +10.5%. Take a look here: http://spreadsheets.google.com/ccc?key=pBCH2ClzmrpkkgDXSggZYEQ&hl=en

I was trying to stay within the example. You have a vehicle with known gear ratios, weight, drive wheel radius. You are provided a horsepower curve. That's what you have to work with. So to match a given point on the power curve with momentum you need the gear ration and drive wheel radius...

That formula contains the conversion back to force (and requires calculating the velocity to find momentum). Momentum / velocity = force. So far I haven't seen a formula that fills the criteria, and I've been looking a long time. Thanks for the reply.

So I should have collected a bunch of half-baked and incorrect formulas?! It's a simple question. Let me restate it this way: In the example in the spreadsheet, can a single, consistent formula be written that calculates acceleration from power without converting power to force? If not...

We're now in Zen-land, and the answer is that the car has nowhere to go.

The original question is, knowing power in that example can you calculate acceleration without first converting back to force? The answer is no. You need the total reduction of the driveline (including the drive wheel radius) and the RPM. Fair enough, you need that to calculate acceleration...

Cyrus, they all fall apart. Most commonly the conversion from power back to force is imbedded in them, so they fail by definition. The others, most commonly based on energy change, do work after a fashion, but the results are ambiguous: The same amount of energy changenproduces different...

In fact, knowing the rear wheel horsepower and the gear does not yield a workable solution. As is pointed out in the spreadsheet, at a given engine horsepower the rear wheel horsepower is identically the engine horsepower in all six gears. Useful, nope. But it is interesting. The formula...

A little out of my field, but try this: Gravitational attraction is due to the warping of space. Things roll "downhill" toward objects with mass. The mass of the rolling things adds to the steepness of the well sides (warping of space). The potential energy of an object changes relative to...

This is a very old topic that I wanted to "publicize". My contention is that you cannot use power to calculate acceleration without first converting power to force. It is possible to calculate an acceleration by assuming some period of time to calculate a change in energy, but this method does...