Some cool Speed trivia

[MikeW]

I agree with Stephen. From the earlier thread that I posted it mentioned that the current world record for a top-fuel dragster was 4.441 seconds for the quarter mile. The following formula shows the average speed:

There are 3600 seconds in an hour.

3600 / (4.44100 * 4) = 202.657059 mph average speed.

Therefore, if the covette averaged exactly 200mph for the same quarter mile the dragster wins. However, it's very, very close.

(3600 / 200mph) / 4 = 4.5sec

As you can see, the dragster only wins this by

4.5 - 4.44100 = 0.059 sec

During that 0.059 sec, the Vette, at exactly 200 mph only has to go a short distance to the finish line:

((200 * 5280) / 3600) * 0.059 = 17.3066667

The Vette only had to travel 17.3 more feet to reach the finish line. That's about one car length.

There's no way that the dragster passed the Vette within 3 seconds as claimed. While that would be theoretically possible since we don't have an acceleration graph, I highly doubt it. For that to work, the dragster would have to accelerate to far more than 200 mph, pass the Vette at the 3 second mark, and then slow way down to 200mph or less in order to cross the finish line just 17 feet ahead more than a second later.

[TomoHawk]

The dragster's finish speed is more like 300 MPH, so the average speed doesn't coount, and the dragster passes the Corvette at more than 200 MPH and finishes way ahead. Remember, the speed is measured during the last 66 feet of the way, so the dragster could still be accelerating or gaining.

If the dragster averaged 202 MPH, then it would defintely need the whole track to catch the Corvette, in it even does.

[panchovisa]

Tomo, your right the average speed doesn't count. In fact the final speed doesn't count either (300mph or 500mph). What does count is elapsed time (same as in real drag racing).

MikeW has given you all that is important, the dragster wins by 17' and .059 seconds. If the 1/4 mile were 18' shorter the Vette wins. In fact 15 or 16' shorter should do (assuming the dragster is still accelating at the finish line)

[MikeW]

The dragster's finish speed is more like 300 MPH, so the average speed doesn't coount, and the dragster passes the Corvette at more than 200 MPH and finishes way ahead.

I'm sorry but that's simply not correct. The dragster's finish speed was actually 332.34 mph but the average speed most certainly counts.

If the dragster averaged 202 MPH, then it would defintely need the whole track to catch the Corvette, if it even does.

The dragster did average 202 mph. That's what I was demonstrating. If the dragster averages more than the Corvette it wins. Less it loses. There are absolutely no "if's" here.

This is the data used in the Corvette comparison which you posted. I can't find evidence of a newer record set since 2003. Here's a link to the raw data:

http://www.nhra.com/2003/events/race18/index.html

If you can demonstrate that my calculations are incorrect I'd be more than happy to admit I'm wrong.

[MikeW]

Tomo, your right the average speed doesn't count. In fact the final speed doesn't count either (300mph or 500mph). What does count is elapsed time (same as in real drag racing).

I think you'll find that average speed exactly corresponds to the elapsed time over a fixed distance. If you want some wiggle room you can claim that one car might not drive as straight and therefore had a higher average speed because he drove a longer distance to reach the same finish line. That would be the only case where average speed doesn't count.

[TomoHawk]

You guys are TOTALLY off the point.

The average speed or the elapsed time has NOTHING to do with the example. The point being made is the the dragster can and DOES accelerate to such a speed that it catches the Corvette. Current NHRA, IHRA, or any other records have NO place here. I can make a similar point with a jogger and a cyclist.

If you have a beef with the point, why don't you contact the person who originally put this fact on the Internet and argue with HIM. I have the mathematical proof right here on my table. You can calculate any kind of speed or time you like, but the dragster still catches the Corvette and passes it long BEFORE the finish line.

thx

[MikeW]

You can calculate any kind of speed or time you like, but the dragster still catches the Corvette and passes it long BEFORE the finish line.

If you consider 25 or so feet to be long before the finish then I'll happily agree with you. If not there seems like no point in discussing this further.

[TomoHawk]

Then we are done here. Your calculations (however basic) are correct, but don't support the author's point.

Actually, the dragster passed the corvette going at much more than the Corvette's 200 MPH, maybe like 350 MPH ( for example), with a final finish speed of over 500 MPH. Not the exact speeds, I would have to calculate them. Gives you an idea.

[sblake01]

The authors point borders on being a crock. Like I said in my frist post in this thread, the TF car wins but not by much. 4.5 seconds is 4.5 seconds, no matter how fast your going.

Bill, don't confuse fast with quick.

[panchovisa]

MikeW, I made the statement about average and top speeds to Tomo only to get the point across that elapsed time is what he should wrap his mind around. Of course I know that speed is distance divided by time (which is an average for that distance, or that time).

People fixate on speed without knowing what it is. And when they get confused they argue acceleration (which is what they don't understand squared!).

[TomoHawk]

Add to that there is no thing as decceleration, which is just negative acceleration. You can also throw in "centrifugal force," which doesn't exist!

[MikeW]

MikeW, I made the statement about average and top speeds to Tomo only to get the point across that elapsed time is what he should wrap his mind around.

I understand what you meant now and you are absolutely right. What I interpreted you as saying was that it "doesn't matter what the average speed is" when in fact you were saying that it "doesn't matter what the average speed is in order to determine the winner". Absolutely. The elapsed time is all that matters.

Most of us seem to agree with Stephen's original assertion that this hypothetical example represents a really close race. I was just attempting to put some numbers to it. If the race were a bit shorter than a quarter mile the Corvette would win. Any longer and the dragster would win by an even bigger margin.

I've done some more calculations and it appears that in the worst case the dragster pulls ahead at approximately 4.35 seconds and 1276 feet into the race which is 44 feet from the finish line. This assumes that the dragster has stopped accelerating by this point and has reached its maximum velocity of 332mph for the last 50 feet of the track. If it is still accelerating when it takes the lead then the crossing point becomes even closer to the finish line.

The original author's hypothetical example of a dragster making a standing start against another car with a head start which is already up to top speed and winning certainly puts the awesome acceleration of the dragster into perspective. I was amazed by the figures the first time this information was posted. Unfortunately the assertion

"within 3 seconds the dragster catches and passes you"

is simply untrue and the statement

"but the dragster still catches the Corvette and passes it long BEFORE the finish line"

is misleading and ambiguous at best.