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bsnalex
18th May 2013, 19:28
Only started watching racing and indycar last year...why on ovals, is qualification based on average speed? Why not just base it on fastest time in 4 laps? Also, how do they clock the average speed? Average of every second? Speed when crossing the line?p

Nem14
18th May 2013, 20:07
They show average speed because the general public can't relate to a lap time like 39.25 seconds.
A 39.25 second lap on a 1.5 mile oval would be a much slower average speed than a 39.25 on the 2.5 mile Indy oval.

Average speed is calculated from the lap time. The drivers look at lap time, not average speed.
The goal is to make a lap in the shortest possible time.

At Indy, a 40.000 second lap time = 225 mph average speed

It's a 2.5 mile lap, or 13200 feet.

13200 feet / lap time x 60 sec x 60min / 5280 feet per mile = average speed in miles per hour.

13200 feet / 40 seconds x 60 seconds x 60 minutes / 5280 feet per mile = 225 miles per hour

Will Power did 4 laps in 2:37.3127 (157.3127 seconds - an average of 39.328 per lap). His fastest lap was done in 39.2290 seconds

His 4 lap average speed was 288.8425 mph. His fastest lap (lap #1) was an average speed of 229.4221 mph

Nem14
18th May 2013, 21:06
Oops!

His 4 lap average speed was 228.8425 mph, not 288.8425. LOL!

jackmart
18th May 2013, 21:14
So I thought they could go back out and try again. So now they are done trying to get into the top 9?

Nem14
18th May 2013, 21:41
4-lap qualifying until 6:00 PM EST.
Wind is not much of a factor today, but some will wait for the air temp to drop some so the engines can make a tad more power.

Top 9 pole shootout starts at 6:30 PM EST.

bsnalex
18th May 2013, 22:20
They show average speed because the general public can't relate to a lap time like 39.25 seconds.
A 39.25 second lap on a 1.5 mile oval would be a much slower average speed than a 39.25 on the 2.5 mile Indy oval.

Average speed is calculated from the lap time. The drivers look at lap time, not average speed.
The goal is to make a lap in the shortest possible time.

At Indy, a 40.000 second lap time = 225 mph average speed

It's a 2.5 mile lap, or 13200 feet.

13200 feet / lap time x 60 sec x 60min / 5280 feet per mile = average speed in miles per hour.

13200 feet / 40 seconds x 60 seconds x 60 minutes / 5280 feet per mile = 225 miles per hour

Will Power did 4 laps in 2:37.3127 (157.3127 seconds - an average of 39.328 per lap). His fastest lap was done in 39.2290 seconds

His 4 lap average speed was 288.8425 mph. His fastest lap (lap #1) was an average speed of 229.4221 mph


You missed my main question though, how do they calculate the average speed? Are they taking into account that at one point he was moving 1 mph?

I think it's a bit silly to think the general public doesn't understand a timed lap, all courses are different lengths.

Starter
18th May 2013, 22:34
You missed my main question though, how do they calculate the average speed? Are they taking into account that at one point he was moving 1 mph?

I think it's a bit silly to think the general public doesn't understand a timed lap, all courses are different lengths.
The cars are never doing one MPH because the timed laps are flying laps, not from a dead stop.

Nem14
19th May 2013, 04:33
You missed my main question though, how do they calculate the average speed? Are they taking into account that at one point he was moving 1 mph? I didn't miss anything - "Also, how do they clock the average speed?."

I showed you exactly how to calculate the average speed of a timed lap, even if the car starts from 0 mph, on an oval OR A ROAD COURSE. Even if the car stops at any time during the lap, and then starts moving again.
An AVERAGE speed takes into account ANY speed the car travels during a timed lap.

As Starter points out - they get a partial pit out lap, and an entire warm up lap, BEFORE they start timing the 4 laps that count towards qualifying.
None of the cars today went slower than 210 mph on any 4 of their qualifying laps, so I'm not sure where you come up with 1 mph?

C3PO
19th May 2013, 14:23
You missed my main question though, how do they calculate the average speed? Are they taking into account that at one point he was moving 1 mph?

I think it's a bit silly to think the general public doesn't understand a timed lap, all courses are different lengths.

When the auto racing stated in the USA and Europe as well, it was all about top speed and avarage speed records. In these times the general public doesn't understand and doesn't care about lap times, track shape, track length etc.

Don Capps
19th May 2013, 14:38
When the auto racing stated in the USA and Europe as well, it was all about top speed and avarage [sic] speed records. In these times the general public doesn't understand and doesn't care about lap times, track shape, track length etc.

Actually, this statement is both wrong and rather a bit of Enthusiast twaddle, especially when it comes to the United States, there being ample evidence to the contrary given that the citing of lap times and circuit distances was commonplace during the first quarter century of automobile racing, to circa 1920.

call_me_andrew
20th May 2013, 02:08
I think it's a bit silly to think the general public doesn't understand a timed lap, all courses are different lengths.

There's a difference between understanding something and being able to relate to something. For example, I understand the universe is expanding, but I can't relate to the notion that distances are in a constant state of flux on such a large scale.