Speed Limit Enforcement: Setting an Example for Adherence to Laws

In summary: UNDER the speed limit?In summary, the conversation discusses the issue of the speed limit and its enforcement. It is argued that the disregard for the speed limit sets a bad precedent for adherence to other laws and can lead to dangerous situations. The cost and effectiveness of enforcing speed laws is also debated, with suggestions for camera surveillance systems. There is also a mention of people's tendency to go over the speed limit and the pressure to conform to the average speed of traffic.
  • #36
chayced said:
Speed limits do not go down when road conditions are bad, such as congestion, rain, ice, or pedestrians.
There are electrically-powered remote-controlled signs on I-95 here in Maine that are used to reduce speed limits under just such conditions. Apart from the interstate, though, such signs are rare, except around road construction.
 
Physics news on Phys.org
  • #37
chayced said:
That's why I recommend using reckless driving laws instead of speed limits. The biggest problem with this is it requires the courts and the lawmen to use common sense.

Speed limits do not go down when road conditions are bad, such as congestion, rain, ice, or pedestrians.

Speed limits also do not go up when road conditions are good.

Speed limits themselves do not solve people who tailgate, pass in breakdown lanes, or people who drive obscenely fast through a pack. Each of these things can happen easily without the offending driver breaking the speed limit as is seen every day in major traffic.

I agree that 2% of the drivers ruin it for all of us, but they can do it just as well below 55 as they can above 55.

What about the slow driver who's afraid to turn left in a traffic area? This creates a HUGE line up behind them. This also a problem.

You guys keep pointing out the same thing, which gets old. Everyone is bad in their own way.

The best of drivers have their eyes OPEN and is CONFIDENT about driving.

Just because you drive the speed limit does NOT imply you are driving safe. Most of the people I see driving speed limit NEVER check their blind spots. They also NEVER merge onto the highway at proper speeds and treat the acceleration lane like a city street. They also BRAKE on the highway for anything sudden. (Brakes on the highway is EXTREMELY dangerous and I have NO IDEA how people are at ease at slamming breaks when traffic is moving nicely.)

Note: Being over confident is just as bad as lacking confidence.
 
  • #38
Ouabache said:
I used the drive the speed limit or slightly over until I researched about speed and gas milage efficiency about three years ago. So on an interstate with maximum of 65mph, I'll drive 55 out of choice. I can drive the same distance (as those driving 65 and over) and reduce the amount of CO2 emitted per mile, while at the same time, save money at the pump. So I am lowering my 'carbon footprint' and pay less per mile for gasoline. Now that I have been driving this way for 3 years, my gas-pedal foot has been conditioned to go no faster than 55. I do stay in the slow lane to allow passing traffic to go by.

(footnote: In general, I find it safer to drive in one of the edge rather than center lanes, due to the fact that you have one less lane along side you to be aware of).

There's a cost/benefit trade-off.

On daily trips, the few minutes you save every trip by going faster aren't worth the extra fuel cost, especially since those trips are on roads with more traffic that you have to worry about. Driving the same speed as traffic flow is still preferable, both because of safety and the frustration factor (drivers cut in front of you, forcing you to slow down to allow a safe margin between you and the driver ahead of you, encouraging the driver behind you to pass you and cut in front, etc until you feel like you're driving backwards - driving slower than the flow of traffic causes frustration for everyone involved).

On long cross-country trips on the interstate, an extra 10 mph winds up saving a lot of driving time. With most of the trip being in between cities, the risk of an accident rises an almost negligible amount. The only question becomes how much money per hour is that saved time worth to you. If you're shortening a trip from 12 hours to 10 hours, it's the last two hours you're saving. Considering you'd probably be driving tired those last two hours, eliminating them is worth the extra money in fuel.
 
  • #39
186 Thousand Miles Per Second.

It's not only a good idea. It's the Law !
 

Attachments

  • speed5mr.jpg
    speed5mr.jpg
    20.7 KB · Views: 336
  • #40
BobG said:
If you're shortening a trip from 12 hours to 10 hours, it's the last two hours you're saving.
To go the same distance as 12 hours at 65 mph, you would need to go 78 mph to save 2 hours. If you take breaks, you need to go faster.
 
  • #41
jimmysnyder said:
To go the same distance as 12 hours at 65 mph, you would need to go 78 mph to save 2 hours. If you take breaks, you need to go faster.

Yeah, also the one going 65mph also has to take breaks. You seem to have forgotten that part too.
 
  • #42
sketchtrack said:
If we go with electric cars to replace oil burning cars, then we won't need a speed limit.

What?
 
  • #43
brewnog said:
What?

There are really fast electric cars out there. There is one who does 0-60mph under 4 seconds!
 
  • #44
JasonRox said:
There are really fast electric cars out there. There is one who does 0-60mph under 4 seconds!

There sure are, but we have yet to have a fast electric car that either has a long range or is easy to fill up. The faster the car goes the less efficient it gets, that means that in order for me to have a car capable of highway speeds, a necessity where I drive to get to work, I can't get the range to get to work and back home. Now I could invest in a car several times what I am able to pay to get both range and speed, but it's more expensive than the gas driven alternative and the gas to drive it by almost a factor of ten.
 
  • #45
chayced said:
There sure are, but we have yet to have a fast electric car that either has a long range or is easy to fill up. The faster the car goes the less efficient it gets, that means that in order for me to have a car capable of highway speeds, a necessity where I drive to get to work, I can't get the range to get to work and back home. Now I could invest in a car several times what I am able to pay to get both range and speed, but it's more expensive than the gas driven alternative and the gas to drive it by almost a factor of ten.

Some have a range of 100 miles. How freaking far do you work?
 
  • #46
JasonRox said:
Yeah, also the one going 65mph also has to take breaks. You seem to have forgotten that part too.
No he didn't. Please do the math first.
 
  • #47
Gokul43201 said:
No he didn't. Please do the math first.

How many breaks did the guy doing 65mph take?

How many breaks did the guy doing 78mph take?

How long were they?

If the guy doing 65mph takes an hour lunch because he wants to be well rested to continue his long trip of 11 hours (12 total), then you certainly don't need to do 78mph to match him.

I don't see how you can account for breaks in the math without even mentionning what they are!
 
  • #48
JasonRox said:
Some have a range of 100 miles.
Are those the ones that also do 0-60 in 4s?
 
  • #49
JasonRox said:
How many breaks did the guy doing 65mph take?

How many breaks did the guy doing 78mph take?

How long were they?
Equal number of breaks by both guys, any length (equal lengths for both guys) you want.
 
  • #50
Gokul43201 said:
Equal number of breaks by both guys, any length (equal lengths for both guys) you want.

A guy on the road for 12 hours is more likely to take more breaks.

I driven from Quebec City to Niagara Falls, taking a total of 15 minutes of breaks. That's total complete stopping time and I made it in record time. Others who go slower stop frequently and make it in terrible time.
 
  • #51
JasonRox said:
A guy on the road for 12 hours is more likely to take more breaks.
I guess that's possible. Under good conditions, I will take a short break after every 4-5 hrs of driving.
 
  • #52
JasonRox said:
Yeah, also the one going 65mph also has to take breaks. You seem to have forgotten that part too.
I meant that if you go on a 12 hour trip and travel at 65 mph you will cover 780 miles. To do that in 10 hours you would have to go 78 mph. If you take 1/2 hour break, then you are only spending 11.5 hours out of the 12 actually moving. You would cover 747.5 miles. To do that in 10 hours with a half hour break, you would need to travel at 78.7 mph. The longer you break, the faster you must go to save 2 hours.
 
  • #53
Gokul43201 said:
Are those the ones that also do 0-60 in 4s?
Yes, 0-60 in 3.9 sec, 220 miles on one charge.

http://www.teslamotors.com/
 
  • #54
jimmysnyder said:
I meant that if you go on a 12 hour trip and travel at 65 mph you will cover 780 miles. To do that in 10 hours you would have to go 78 mph. If you take 1/2 hour break, then you are only spending 11.5 hours out of the 12 actually moving. You would cover 747.5 miles. To do that in 10 hours with a half hour break, you would need to travel at 78.7 mph. The longer you break, the faster you must go to save 2 hours.

Yeah, but under those calculations the 12 hour guy never took breaks and if he did, he did not cover 780 miles in 12 hours and so he TOO traveled 1/2 hour over.
 
  • #55
JasonRox said:
Yeah, but under those calculations the 12 hour guy never took breaks and if he did, he did not cover 780 miles in 12 hours and so he TOO traveled 1/2 hour over.
No. I meant that if he traveled over a 12 hour period and took a half hour break then at the end of his 12 hour trip he would have traveled for 11 and a half hours and rested for 1/2 hour. He would cover 747.5 miles in 12 hours and then his 12 hour trip would be finished. He would not go on, he would be done with his trip. If his competitor wanted to arrive 2 hours earlier, that is a 10 hour trip, also with 1/2 hour rest, then he would travel for 9.5 hours and rest for 1/2 hour. Then he would be finished. He would be done 2 hours earlier than the one who took a 12 hour trip with a 1/2 hour rest in it. He will need to go 78.68 mph in order to achieve it. The longer the rest, the faster you must go:

11.5 hours of actual travel time during a 12 hour journey at 65 mph is 747.5 miles.
9.5 hour of actual travel time during a 10 hour journey of 747.5 miles requires 78.68 mph.
The longer the breaks, the faster the speed.
 
  • #56
Ouabache said:
I used the drive the speed limit or slightly over until I researched about speed and gas milage efficiency about three years ago. So on an interstate with maximum of 65mph, I'll drive 55 out of choice. I can drive the same distance (as those driving 65 and over) and reduce the amount of CO2 emitted per mile, while at the same time, save money at the pump. So I am lowering my 'carbon footprint' and pay less per mile for gasoline. Now that I have been driving this way for 3 years, my gas-pedal foot has been conditioned to go no faster than 55. I do stay in the slow lane to allow passing traffic to go by.

(footnote: In general, I find it safer to drive in one of the edge rather than center lanes, due to the fact that you have one less lane along side you to be aware of).

jimmysnyder said:
I meant that if you go on a 12 hour trip and travel at 65 mph you will cover 780 miles. To do that in 10 hours you would have to go 78 mph. If you take 1/2 hour break, then you are only spending 11.5 hours out of the 12 actually moving. You would cover 747.5 miles. To do that in 10 hours with a half hour break, you would need to travel at 78.7 mph. The longer you break, the faster you must go to save 2 hours.

1) You need to compare 55 mph to 65 mph, not 65 mph to 75 mph.

2) It's an approximation. You can't know how many breaks and how long the breaks for any given driver are.

The driver has to take at least one break, since very few cars can get 600+ miles on one tank of gas.

If the driver takes a break every 4 hours, he has to take 2 breaks whether he travels 10 hours or 12 hours. If the breaks are 15 minutes, then the driver driving 55 covers 632.5 miles. The 65 mph driver can cover the same distance with 2 15 minute breaks in 10.23 hours.

If the driver takes a break every 2 hours, he has to take 5 breaks in 12 hours and only 4 breaks in 10 hours. If the breaks are 15 minutes, then 55 mph driver covers 591.25 miles. The 65 mph driver covers the same trip in 10.1 hours.

If it's a family vacation and both drivers leave at 10 PM:

55 mph driver: The 55 mph driver can cover 426.25 miles with one 15 minute stop for gas by 6AM when the kids and the wife wake up. At 6AM, the kids and the wife wake up and he has to take a 30 minute break for breakfast, drives 55 for 15 minutes and 13.75 miles when the youngest kid informs the car that they forgot to use the bathroom, hence another 15 minute break. The 55 mph driver then drives 55 miles between 7 AM and 8 AM before the wife has to use the bathroom. The oldest kid suddenly remembers they have to use the bathroom as soon as the 55 mph driver starts the car. 5 minutes later the 55 mph driver starts to pull out of the parking space when the 2nd oldest screams that the dog is still leashed to the rear bumper. The 55 mph driver is finally back on the road at 8:30 AM and it's 9:30 AM before anyone else has to use the bathroom. Strong swear words can suppress the urge to urinate for at least 30 minutes, meaning the 55 mph driver can keep on driving, covering 82.5 miles over the last 90 minutes. Total distance covered: 577.5 miles.

65 mph driver: The 65 mph driver can cover 503.75 miles with one 15 minute stop for gas by 6AM when the kids and wife wake up. At 6 AM, the kids and wife wake up and whine about eating. While strong swear words can only suppress urination for 30 minutes, they can suppress hunger for one hour, 13 minutes and 43 seconds. The 65 mph driver covers the remaining 73.75 miles in 1 hour and 8 minutes, arriving at 7:08, more than 5 minutes before reaching the limit of appetite suppression. Total time saved: 2 hours 52 minutes.

The key difference: Driving at 55 mph when the family is asleep yields an average distance of 53.28 miles each hour. Driving at 55 mph when the family is awake yields an average distance of 35.35 mph, except on the last final burst to the destination when the average distance traveled once again increases to 55 miles over the last hour regardless of whether one of the kids pees their pants, the dog pukes, or the wife announces she's divorcing the driver.

Driving at 65 mph when the family is asleep yields an average distance of 63 miles each hour. Driving at 65 mph when the family is awake yields an average speed of 41 miles every hour except on the last final burst to the destination when the average distance increases to 65 miles over the last hour regardless of who died.

Edit: Sigh. Probably won't get there no matter how fast or slow we travel. http://www.xkcd.com/461/
 
Last edited:
  • #57
BobG said:
1) You need to compare 55 mph to 65 mph, not 65 mph to 75 mph.
BobG's message #38, the one I originally responded to spoke of the interstate hwy. I can't speak for the whole country, but that means 65 mph around here, that's why I chose it. Remember, we are speaking of a roughly 12 hour stretch of road. BobG's message also spoke of going 10 mph over the limit. However a 12 hour journey at 55 mph will go 660 miles. In order to cover that in 10 hours you would have to go 66 mph, still outside of the pale. If there are breaks, then you will need to go faster than 66 mph.

Edit: Sorry Bob, I thought I was responding to JasonRox.
 
  • #58
jimmysnyder said:
BobG's message #38, the one I originally responded to spoke of the interstate hwy. I can't speak for the whole country, but that means 65 mph around here, that's why I chose it. Remember, we are speaking of a roughly 12 hour stretch of road. BobG's message also spoke of going 10 mph over the limit. However a 12 hour journey at 55 mph will go 660 miles. In order to cover that in 10 hours you would have to go 66 mph, still outside of the pale. If there are breaks, then you will need to go faster than 66 mph.

Edit: Sorry Bob, I thought I was responding to JasonRox.

Actually, my message spoke of an "extra 10 mph", not 10 mph over the speed limit. I would never encourage people to break the law.

Besides, if you go 10 mph over the speed limit, you're sure to rear-end Oubache who will be traveling 20 mph slower than you. That would drastically increase the travel time for both of you.

Additional besides, the original problem used speeds with only two significant digits. Whether you're traveling 75 instead of 65 or 65 instead of 55, the trip is still shortened to 10. hours.

That's my story and I'm sticking to it.
 
  • #59
Chi Meson said:
I concur with Hurkyl. Left to themselves, SOME people in the group will consider themselves special (they already do) and tailgate, pass in the breakdown lanes, drive obscenely fast through a pack, etc. etc.

98% of any group is fine. They follow generally accepted rules of the road (official and unofficial). We absolutely need the laws that hold back the self-appointed "special people" among us.
By my casual observation in Maryland, 98% is far too high. Tailgating is the norm, even to the extent that they pack tightly together when merging onto a freeway, and they will not pass you until after they start tailgating you.

It's not that these people feel they're special. It's (most likely) that the popular opinion is that it's not something worth caring about, so they remain uneducated and unaware of their bad behaviors.
 
Last edited:
  • #60
Hurkyl said:
By my casual observation in Maryland, 98% is far too high.

Well you know, 57% of all statistics are made up on the spot. (I heard that here some time ago). I agree that I was being a little too gracious.
 
  • #61
Hurkyl said:
By my casual observation in Maryland, 98% is far too high. Tailgating is the norm, even to the extent that they pack tightly together when merging onto a freeway, and they will not pass you until after they start tailgating you.

It's not that these people feel they're special. It's (most likely) that the popular opinion is that it's not something worth caring about, so they remain uneducated and unaware of their bad behaviors.

Hey, you leave me and my Murryland drivers alone! Slow poke...

Looks like YOU got schooled on how to drive in MD!
 
  • #62
Cyrus said:
Hey, you leave me and my Murryland drivers alone! Slow poke...

Looks like YOU got schooled on how to drive in MD!
Huh? This doesn't even make sense. Unless... you're not one of those people who haven't figured out how to pass someone without tailgating, are you? :wink:
 
  • #63
Hurkyl said:
Huh? This doesn't even make sense. Unless... you're not one of those people who haven't figured out how to pass someone without tailgating, are you? :wink:

This is why people tail gate and flip you off in MD...

LeftLane.jpg


Because people don't know what damn lane to drive on! I live next to a lot of old people. My god they are horrible. The speed limit on my road is 50mph. They *LOVEEEE* to drive side by side going 40mph. I have to ride their a** until a gap opens up so I can change lanes around them. Damn old people...

If someones going slow on the slow lane, I leave them alone. If they go slow on the fast lane, I am an absolute a-hole to them. I only cut them slack if they have kids in the back seat.

Most of the offenders are stupid middle aged people driving around 5-10 below the speed limit.
 
  • #64
I call it slipstreaming not tailgating. :biggrin:
 
  • #65
Cyrus said:
This is why people tail gate and flip you off in MD...
People tailgate everyone in MD, not just me. Try actually paying attention to the other drivers on the road sometime. :-p


If they go slow on the fast lane, I am an absolute [edited for content] to them.
If you ride my bumper while I'm in the fast lane passing a group of people, I'm probably going to slow down until I can get back over, so that's quite counterproductive. :-p

(And I think the word you're looking for isn't 'slow', but 'legally')
 
  • #66
Hurkyl said:
People tailgate everyone in MD, not just me. Try actually paying attention to the other drivers on the road sometime. :-p

Its hard to do that when you're too bussy tailgating! :rolleyes:

I have a pet peeve of driving next to other people. I'll accelerate until I'm a good 10-15 car lengths ahead of you and then go the speed limit or match your speed so you never catch up to me. I can't stand being inside the pack of idiot's who are too indecisive to change lanes, slow down for no reason, or do various other stupid driving habbits.

Hey look at me, I've got my blinker on for 5 mins now and I STILL can't change a lane. :rolleyes: Meanwhile, I could have driven a bus through there...
 
  • #67
Come to think of it, I drive as fast as I possibly at all times. But living in South Florida this turns out to be 10-15 mph below the speed limit.
 
  • #68
ekrim said:
Come to think of it, I drive as fast as I possibly at all times. But living in South Florida this turns out to be 10-15 mph below the speed limit.

HAHAHHAHAh...I know the feeling man... damn old people.
 
  • #69
Cyrus said:
HAHAHHAHAh...I know the feeling man... damn old people.
My dad is a lead-foot and at 82 years of age, he just bought a 1997 Park Avenue Ultra with a 232ci V-6 that is supercharged and develops 240 hp and WAY more foot-pounds of torgue. If you're up here, he won't flip you the bird (he's too nice for that crap) but you will be looking at his rear bumper. I'm trying to slow him down, but it's tough.
 
  • #70
turbo-1 said:
My dad is a lead-foot and at 82 years of age, he just bought a 1997 Park Avenue Ultra with a 232ci V-6 that is supercharged and develops 240 hp and WAY more foot-pounds of torgue. If you're up here, he won't flip you the bird (he's too nice for that crap) but you will be looking at his rear bumper. I'm trying to slow him down, but it's tough.

Good for him! Let him drive fast. Hahaha, he's got the classic old's-man-mobile - nice. Old people are attracted to that car like white on rice.
 

Similar threads

Replies
15
Views
2K
Replies
30
Views
7K
Replies
69
Views
12K
Replies
46
Views
8K
Replies
26
Views
8K
Replies
152
Views
7K
Replies
16
Views
6K
Replies
3
Views
3K
Back
Top