2 questions regarding traction and accidents

Everytime I have heard "Don't be the first to the scene of the accident " has been in relation to following distance and/or defensive driving. It means take your time, keep your distance and leave yourself an out.

 

If the situation where it's 20 degrees on sandstone and winter weather up there and people are laying in the median along the rocks bleeding and sometimes with bone sticking out of their limbs you grab a blanket or two and see what you can do even if it's keeping them calm until the EMT gets there. (That will take a certain amount of time) If necessary your cab becomes a place to keep the uninjured people warm until the help gets there.

The problem with stopping is if you get involved and start touching people who are either dead, close to it or hurt really bad and cannot be moved and don't know what you are doing (No CPR training etc) then you expose yourself to liability later. There is a fine line between being there to provide a moral or emotional support and backing off when the professionals do arrive.

If a vehicle is burning and fully involved and you happen to have a cargo that is flammable or hazmat etc you don't want to be around period. If there are people being burnt to death and you can hear them, well it's better you did not stop. You might have some trouble sleeping a while. Isnt nothing you can do for them anyway.

Should I go on? There are times Ive stopped where it's possible to help but there were also times I did not stop at all. The biggest part of that is because I am a million plus dollars in narcotics and it will expose the load to risks beyond reason to stop or worse get out and leave it unattended. there will be people that will stop. I keep moving. That does not mean I don't feel sad for them or bad or whatever. But that truck and load keeps moving.

 

I would add the hardest to stop is a bobtail. Then pulling empty trailer. The most easy to stop is fully loaded trailer.

That because they are designed to stop fully loaded. When you're bobtailing you have to many tires on the ground for the weight. So the drive tires can't grip the payment. They actually just slide across on top of the pavement like in snow.

 

I don't want to sound like a prik, but the word you're looking for is, "momentum", which is velocity X speed. The explanation of inertia will be in next week's class.

 

Thank you I was trying to think what the word was.

 

Actually, Momentum is Mass x Speed. what we are really discussing is kinetic energy. Just thinking about all of these formulas is giving me another headache.

 

I don't want to sound like a prik, but the OP used the term properly.

Inertia is the property of mass that causes resistance to any change in velocity.
Your equation for momentum fails to take the mass of the object into consideration, and the mass can not be ignored.

In fact, your equation fails in more than that.
Velocity is the rate at which an object changes its position.
Speed refers to relative motion of an object.


When the OP questions the 'truth' about a heavy load stopping in a shorter distance than a light load, well, it would depend on a few factors that deal with how much energy is needed/available and how much control the driver has with both types of loads.

In my own experience I find that a lighter load will stop more quickly if I am applying the brakes correctly.

 

Thank you for writing, I was beginning to wonder.

I must remember to say that if you hit someone with your rig or vehicle or even a bike (Ive actually have had people badly hurt under my wheels of a bike.. those are stories that wont see the internet, the one did live but he was critical for 5 months that year only 10. Busted skull leaking blood and hemotobias under the hair and skin area and eardrums were ruptured as well. When someone is that bad hurt you keep them warm and send someone for help, I think they life flighted him from the local hospital when the life threatening injuries became apparent beyond their ability. It's been many years but I never did forget that boy.

What I am getting at in a roundabout way, if you hit someone you do have a duty to stop. Otherwise you commit a crime by running away.

I remember one wreck in Illinois about a hour south and west of chicago on 55. A obese lady was partially ejected from a smaller pickup through the back glass. The truck landed on it's roof almost cutting her in half at the stomach region almost to the spine. The bed being upside down had hung her against her spine and against the sharp glass two to three feet above the sloped ground in the median. She had two choices. Breathe and be cut in half or do not breathe, pass out and probably still be cut in half once the body resumes breathing. A driver had reached her, kneeled to hold her head flat. So she can breathe just enough not to be further cut in half. The glass shards kept her guts in place as well. There was no way to move her without Jaws of Life and many trained hands all we can do is monitor that gas dripping from that fill cap above and behind us. It was raining.

I went down about 40 yards to attend her husband who was ejected out, one leg bent broken past normal limits under his body it's not possible for a human to have a leg and knee like that and not scream bloody murder. Therefore I assessed him as either Glasgow Coma Scale of around 5 which is pretty #### low. and found that he needed CPR but due to the position of the body head facing down slope is a blessing and a curse. You could not dare move him because if the big stuff was busted you must assume the spine is also busted. So the first three steps involving the head positioning is out. What I needed was a plastic breather cup designed to force air into anyone's mouth as a defense against infectious and some cases STD oral etc that is part of today's risks with CPR.

A lawman showed up with such a mask and was unwrapping it. I briefed him on the wife in the truck and said I can see about that heart above the landmark on the ribs and wanted to know what his count was. My training was 35 years old at that time and obsololete compared to his. After careful thought of the body I told the officer I cannot do it. The man is past 60 and his ribs wont stand it, I cannot have his ribs punch a lung or heart sac etc and cause bigger problems I did not have that desire in me as bad as he was. Officer told me don't worry help is coming on fast.

I don't know if the man made it he was down too many minutes and we lost about another 6 before the cop got there with the breather, if we did get him resusticated brain damage would have been a REAL and very unwelcome possibility. Better to die naturally than to come back unable to communciate or do anything for the rest of your days.

That is one of the reasons I had to find peace with the idea I did not do CPR on that man. It wont be the first time or the last one. Last one was a month ago when a relative was told that this one needs to get CPR like right now and needed to know if there was a DNR in place. (There was) so that means I back off and say good bye and wait ont he porch for the Law, EMT and County Coroner to arrive. It was about three hours before the body was sufficiently able to be transported. And his dignity was protected I suppose, it was a very public death.

Circling back to the school teaching that you must stop.

Think about that for a moment. If all of us stopped say on the I-495/I-95 split because someone 6 lanes over had a fender bender. If that is the case what are we all going to do about it other than fixing to be a large mass traffic hit and run with some dead and many injuries. Not to mention god only knows how many vehicles fixing to be hit by the horde of barbarians charging towards DC from Jessup-Baltimore at 6 am intent on getting to work.

That's silly. And tragic. You don't stop. Now if it's a fatal or a multipul fatal, and the Law has the road shut in your face and the bodies are left there until the Coronor responds and clears the bodies to be sent to the state crime lab for further autopsy etc. it will take a while, a number of hours. Your driving day there is DONE, you have a certain amount of time left before you must park for your sleeper break. Make a notation that highway closed, fatal such a such a mile marker, route and state.

 

So, do light particles (photons) have any momentum or inertia or kinetic energy, with all that speed?
They are said to have no mass.