Assistance requested of any "rocket scientist" types. I was recently hit in a rearender collision, and one of the legal wrangles I will be faced with is the impact speed. I realise that some cases actually will have an engineer who specialises in accident recontruction. This accident has not resulted in any catastrophic injuries fortunately, so I do not envision an engineer getting involved.
Information that is known that can be part of an appropriate equation is as follows:
The moving vehicle weighs about 2500 pounds. The struck vehicle weighs about 4500 pounds. The impact is directly from behind. The struck vehicle was stationary at the time, and is propelled forward about 20 feet after impact. The brakes stay on for the duration.
One of the "wild cards": surface is a mix of sand and compacted snow, let's speculate an equivalent JBI/CRFI of .3 and temperaure about -5c.
Do we have enough imformation to estimate a speed at point of impact? Do we at least have enough to establish a speed in excess of 5mph/8kph?
PM's cheerfully accepted.
Thanks
question for physics/mathematics wizards
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Captain S itmagnet
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G.N. Thompson
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I'm stricly ametuer, but from ft/pound approach:
X x 2500 = 4500 x 20'
x = 36 ft
so if 36 ' in estimated 2 seconds, thats 18 ft in 1 sec
so 18 x 60 x 60 =64800 ft/hr
divide by 5280 gives a bit over 12 mph???
if someone caught it on video you could get more accurate time.
Hope this helps
GNT
X x 2500 = 4500 x 20'
x = 36 ft
so if 36 ' in estimated 2 seconds, thats 18 ft in 1 sec
so 18 x 60 x 60 =64800 ft/hr
divide by 5280 gives a bit over 12 mph???
if someone caught it on video you could get more accurate time.
Hope this helps
GNT
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200hr Wonder
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Where the wheels locked when the stuck vehicle moved forward or did they spin?
If they where locked then it is easier. If they spun then the energy of the crash was absorbed by the friction between break pad and rotor not between tire and road. In which case the math becomes much more complicated because it would have to depend on the breaking action which is a huge unknown.
FWIW how does speed really make a huge difference in terms of a claim? Your hurt or not, or am I missing something?
If they where locked then it is easier. If they spun then the energy of the crash was absorbed by the friction between break pad and rotor not between tire and road. In which case the math becomes much more complicated because it would have to depend on the breaking action which is a huge unknown.
FWIW how does speed really make a huge difference in terms of a claim? Your hurt or not, or am I missing something?
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mellow_pilot
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On a grade or flat surface? Winter tires or all season? (that one makes only a small difference) Did the struck vehicle rotate at all, or remain straight? Was this at an intersection, did the surface change appreciably (ie were there bare patches from cars traveling other directions)? Were the tire treads caked with snow? How old is the vehicle, is it constructed with crumple zones? Given the weights, I assume it was a truck or other large vehicle being hit by a car, was the larger under cut by the smaller, did it lift the other vehicle at all?
There's a whole lot of variables. That's just off the top of my head (they may not matter at all, but in court people just need to cast doubt). I think you really need to consult an expert if you want an accurate answer which will hold up to legal scrutiny. The police have trained people who do this kind of reconstruction, I'm sure enquiring at your local station could yeild results. Even if they can't help you directly they probably know who can.
I'm pretty sure that rear-end collisions are the fault of the car behind you in all provinces, unless there are some special circumstances (ie one car is backing up). I'm curious as to why you're asking, is there a threshold of speed that changes the claim?
There's a whole lot of variables. That's just off the top of my head (they may not matter at all, but in court people just need to cast doubt). I think you really need to consult an expert if you want an accurate answer which will hold up to legal scrutiny. The police have trained people who do this kind of reconstruction, I'm sure enquiring at your local station could yeild results. Even if they can't help you directly they probably know who can.
I'm pretty sure that rear-end collisions are the fault of the car behind you in all provinces, unless there are some special circumstances (ie one car is backing up). I'm curious as to why you're asking, is there a threshold of speed that changes the claim?
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Captain S itmagnet
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Thanks for the replies so far.
1 I am injured as a result.
2 The tires on the "bullet" car were likely locked up as the road was slippery as mentioned.
3 The road was level.
4 Without getting too specific, the insurer is saying that despite $1800 damage to my vehicle, there is insufficient material damage to warrant a bodily injury claim for restitution from the other party. Their threshold is 5mph/8kph, and they state that the damage is consistent with an impact of less than this speed. I understand that in order for a vehicle to be legally produced and sold in Canada it must demonstrate an ability to have the bumper absorb the total force of such an impact. In my case, a steel bracket which connects the bumper to the frame needed to be replaced. Also there is minor dameage to the steel plate which connects this bracket to the endrailof the frame. The impact zone is a very strudy part of the vehicle.
5 For the record, if I am unable to convince the insurer otherwise, my only recourse in through the courts. Studying case histories in my jurisdiction, virtually all claims whatever the material damage, have been accepted.
6 The impact zone was bumper-on-bumper, not offset. No "over" or "under" direction in energy. ie bumpers of the same height.
7 The "bullet" car is a Toyota Corrola, and the struck vehicle is a Pontiac Montana van, hence the weight difference.
Any further input would be most appreciated.
1 I am injured as a result.
2 The tires on the "bullet" car were likely locked up as the road was slippery as mentioned.
3 The road was level.
4 Without getting too specific, the insurer is saying that despite $1800 damage to my vehicle, there is insufficient material damage to warrant a bodily injury claim for restitution from the other party. Their threshold is 5mph/8kph, and they state that the damage is consistent with an impact of less than this speed. I understand that in order for a vehicle to be legally produced and sold in Canada it must demonstrate an ability to have the bumper absorb the total force of such an impact. In my case, a steel bracket which connects the bumper to the frame needed to be replaced. Also there is minor dameage to the steel plate which connects this bracket to the endrailof the frame. The impact zone is a very strudy part of the vehicle.
5 For the record, if I am unable to convince the insurer otherwise, my only recourse in through the courts. Studying case histories in my jurisdiction, virtually all claims whatever the material damage, have been accepted.
6 The impact zone was bumper-on-bumper, not offset. No "over" or "under" direction in energy. ie bumpers of the same height.
7 The "bullet" car is a Toyota Corrola, and the struck vehicle is a Pontiac Montana van, hence the weight difference.
Any further input would be most appreciated.
This is hardly hold-up-in-court material but I will do my best to prove my hypothesis: "The vehicle must have been travelling faster than 8kph at impact."
Assumptions:
1. Impacting vehicle = #2, Impacted vehicle = #1... mass=m... velocity=v... initial=i.... final=f...
2. Since the impacted vehicle has more mass (9900kg) than the impacting vehicle (5500kg), it is assumed that the two vehicles remained in contact the entire time from impact to "all-stop" - an "inelastic collision".
3. Formula: (M1V1i)+(M2V2i)=(M1+M2)Vf
Plugging in the known values using 8kph = 2.222m/s as the initial velocity of the impacting vehicle:
(9900x0)+(5500x2.222) = (9900+5500)Vf
0 + 12221 = 15000 x Vf
0.814 m/s = Vf
This shows the velocity of the impacted vehicle after the collision is 0.814 m/s. Assuming a frictionless surface, the time taken for that vehicle to travel 20 ft = 6.096m is 7.49 seconds.
If the impacted vehicle stayed in motion for 7.49 seconds after impact the 8kph impact speed is plausible. Since it gives a frictionless surface, and some force would be absorbed by the "crumpling" of the vehicles, I would say that an 8kph impact would not cause the impacted vehicle to move at all. If you went 20 feet ahead I would estimate the impacting vehicle's initial speed was higher than 8kph.
To further "prove" my theory of impact speed:
Using the formula: v2 = u2 + 2as where:
v = final velocity, u=initial velocity @ 8kph, a=acceleration (variable) and s=change in distance:
I calculate an acceleration of -0.405m/s2
Using the formula: x = xi + vi t + 1/2at2 where:
x = distance travelled, xi = initial distance (0 in this case), vi = initial velocity (variable), t=time (2 sec. from another post?), and a=acceleration from above, we get:
6.096 = 0 + vi(2)+0.5(-0.405)(2)^2
going through the numbers this solves for vi = 3.453m or 12.431 kph
Edited:
A coefficient of friction calculation was here but was removed after I discovered an error.
It's messy math and TONS of variables come into play, but that is my attempt at basic physics. It is also very late and it could be jammed full of errors, but there ya go! After all, I am a pilot not a physicist but I was always fairly good at this kind of thing. PM me if you need more info.
Bear in mind that this is a circular equation and should only be used as a general "idea" of what happened... for example if you change the 8kph in the acceleration equation you will in turn throw off all the other equations. I used 8kph as a starting point and as a "figure to use" for vi when I needed it to calculate acceleration. What I am trying to say is at a 15kph collision, a will not be -0.405m/s2 but something else... which will in turn affect the f=ma equation, etc. I did my best but it's all "ballpark"!
I posted this here rather than PM so if anyone sees an error in my logic or calculations it could be pointed out? (Be nice!)
Assumptions:
1. Impacting vehicle = #2, Impacted vehicle = #1... mass=m... velocity=v... initial=i.... final=f...
2. Since the impacted vehicle has more mass (9900kg) than the impacting vehicle (5500kg), it is assumed that the two vehicles remained in contact the entire time from impact to "all-stop" - an "inelastic collision".
3. Formula: (M1V1i)+(M2V2i)=(M1+M2)Vf
Plugging in the known values using 8kph = 2.222m/s as the initial velocity of the impacting vehicle:
(9900x0)+(5500x2.222) = (9900+5500)Vf
0 + 12221 = 15000 x Vf
0.814 m/s = Vf
This shows the velocity of the impacted vehicle after the collision is 0.814 m/s. Assuming a frictionless surface, the time taken for that vehicle to travel 20 ft = 6.096m is 7.49 seconds.
If the impacted vehicle stayed in motion for 7.49 seconds after impact the 8kph impact speed is plausible. Since it gives a frictionless surface, and some force would be absorbed by the "crumpling" of the vehicles, I would say that an 8kph impact would not cause the impacted vehicle to move at all. If you went 20 feet ahead I would estimate the impacting vehicle's initial speed was higher than 8kph.
To further "prove" my theory of impact speed:
Using the formula: v2 = u2 + 2as where:
v = final velocity, u=initial velocity @ 8kph, a=acceleration (variable) and s=change in distance:
I calculate an acceleration of -0.405m/s2
Using the formula: x = xi + vi t + 1/2at2 where:
x = distance travelled, xi = initial distance (0 in this case), vi = initial velocity (variable), t=time (2 sec. from another post?), and a=acceleration from above, we get:
6.096 = 0 + vi(2)+0.5(-0.405)(2)^2
going through the numbers this solves for vi = 3.453m or 12.431 kph
Edited:
A coefficient of friction calculation was here but was removed after I discovered an error.
It's messy math and TONS of variables come into play, but that is my attempt at basic physics. It is also very late and it could be jammed full of errors, but there ya go! After all, I am a pilot not a physicist but I was always fairly good at this kind of thing. PM me if you need more info.
Bear in mind that this is a circular equation and should only be used as a general "idea" of what happened... for example if you change the 8kph in the acceleration equation you will in turn throw off all the other equations. I used 8kph as a starting point and as a "figure to use" for vi when I needed it to calculate acceleration. What I am trying to say is at a 15kph collision, a will not be -0.405m/s2 but something else... which will in turn affect the f=ma equation, etc. I did my best but it's all "ballpark"!
I posted this here rather than PM so if anyone sees an error in my logic or calculations it could be pointed out? (Be nice!)
Last edited by jjal on Mon Jan 08, 2007 1:53 am, edited 3 times in total.
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KISS_MY_TCAS
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GM has built thier vehicles with 5mph bumpers for years, meaning that there be no damage to the bumper itself beyond a 3/8 inch "dent" and 3/4 inch "set" (or displacement) from original position when impacted at 5mph. For your van to have $1800 damage you are well beyond that threshold without me ever seeing the vehicle, been there, done that. Figure the vehicle needs the shock dampers on the bumper reset, the plastic bumper cover replaced and repainted, you aren't gonna be anywhere near $1800 at any reputable bodyshop, if the accident was truly at or below the 5mph threshold the vehicle would need minimal repairs, nothing near the number quoted. Research a reputable source (ie. the US DOT website) about bumper crash standards such as the 5mph bumper, as well as the 2.5mph bumper and you will very quickly have ammo for the insurer. Take a hard copy of the crash standards to the insurer and see how they measure up against your van, it is hard to dispute the numbers that thier standard is based upon if the damage exceeds those values.Captain S itmagnet wrote:Their threshold is 5mph/8kph, and they state that the damage is consistent with an impact of less than this speed
Sounds like a case of your insurer not representing your interests first and foremost. Is this provincial insurance ie. ICBC? Are you both dealing with the same insurance company? It would explain the adjusters need to promote the insignificance of your claim to a minor impact with little damage. Was an accident report filed with the police? Usually rear end accidents are cut and dried. You hit someone and you're at fault. No ifs ands or buts. I would be having a stern chat with my adjuster, and if I wasn't getting results forthwith then I'd sic the lawyer on them.
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niss
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Did his airbag go off? I remember of an incident that went to trial and the guy was convicted because the computer in his car recorded what speed he was at when the crash occured and the airbag deployed.
She’s built like a Steakhouse, but she handles like a Bistro.
Let's kick the tires, and light the fires.... SHIT! FIRE! EMERGENCY CHECKLIST!
Let's kick the tires, and light the fires.... SHIT! FIRE! EMERGENCY CHECKLIST!
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Captain S itmagnet
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Thanks for the contributions.
1 The insurer is in fact ICBC. I am learning that the interests of the liable party are better represented than my interests.
2 My wife has reminded me that the impact was probably not exactly straight on, but canted at an angle of maybe 10 degrees, as the other party was veering in an attempt to avoid the collision. This resulted in a more concentrated impact area. The impact area is also where the endrail of the frame attaches to the rear bumper, a very sturdy part of the vehicle.
3 Although I am weak at math, the theories presented so far concur with my estimate of 10-15mph at impact.
Any further input greatly appreciated.
1 The insurer is in fact ICBC. I am learning that the interests of the liable party are better represented than my interests.
2 My wife has reminded me that the impact was probably not exactly straight on, but canted at an angle of maybe 10 degrees, as the other party was veering in an attempt to avoid the collision. This resulted in a more concentrated impact area. The impact area is also where the endrail of the frame attaches to the rear bumper, a very sturdy part of the vehicle.
3 Although I am weak at math, the theories presented so far concur with my estimate of 10-15mph at impact.
Any further input greatly appreciated.
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tripleseven
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If a 4500 # vehicle is moved 20 feet with the brakes locked by a 2500 # car, I'd say it was travelling faster than 8 km/h. I don't think that it would move 20 ft if on a road covered with fresh freezing rain.
You would have to use the impulse-momentum method, and take into account the coefficient of restitution of the two bumper of the vehicles figure this one out. You also need and accurate coefficient of friction.
You would have to use the impulse-momentum method, and take into account the coefficient of restitution of the two bumper of the vehicles figure this one out. You also need and accurate coefficient of friction.
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mellow_pilot
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Did you get out of the vehicle before an ambulance showed up? That's the key to ICBC. If you wait for the medics, they won't fight you. Doesn't help you now, but thought I'd share for everyone else.
My boss this summer had a similar accident and was paid out because the paramecdics filed a report in addition to the police report.
My boss this summer had a similar accident and was paid out because the paramecdics filed a report in addition to the police report.
Dyslexics of the world... UNTIE!
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Random Flatulation
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Other variables would be the energy absorbed by the car. The bumper would absorb a lot as would the crumple zone if it got that far so you can't just figure out a straight momentum calculation.
The fact that the road was slippery would reduce the damage to your car though. Less friction holding you to the road would mean less force required to move you forward so your bumper wouldn't suffer as much damage before the car is pushed forward. So it may have been a higher speed collision that it would appear from the damage.
The fact that the road was slippery would reduce the damage to your car though. Less friction holding you to the road would mean less force required to move you forward so your bumper wouldn't suffer as much damage before the car is pushed forward. So it may have been a higher speed collision that it would appear from the damage.
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co-joe
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Roger that. Icky Bicky is possibly the worst insurance company to deal with. They are HUGE! In AB one company might insure a hundred thousand drivers and be considered a large player, in BC ONE company insures every car on the road. You're in for a fight, but don't give up... never ever give up! They're counting on you buckling under pressure.Kilo-Kilo wrote:Don't say another word to the adjuster. Get a Lawyer.Captain S itmagnet wrote: The insurer is in fact ICBC.
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Captain S itmagnet
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Thanks all.
The plot thickens, as I am in receipt of a letter today from the "insurer".
"... the physical nature of the impact forces involved in the collision, as well as YOUR PHYSICAL CONDITION AT THE TIME OF THE ACCIDENT ( my emphasis added), has led us to believe... did not result in any compensable injury to you."
"...will not consider any payments with respect to your claim against OUR INSURED (my emphasis again) for injuries..."
For the record, they are in receipt of medical records verifying subjectively and objectively an injury thatis substantial enough to keep me off the flight deck. Obviously that information is being ignored. Besides, what does "physical condition at the time of the accident" mean anyway? An ambulance was not required at the time. Anyone with a modicum of medical knowledge, whch should include the adjustor, knows that an injury to the neck/back/head may take hours or even days to fully manifest itself. The freezeframe of the first few moments after an accident mean squat.
Likelihood of Lawyer involvement greatly increased as of now. I naively thought I was an insured as well with this entity. Lesson learned, lesson shared.
The plot thickens, as I am in receipt of a letter today from the "insurer".
"... the physical nature of the impact forces involved in the collision, as well as YOUR PHYSICAL CONDITION AT THE TIME OF THE ACCIDENT ( my emphasis added), has led us to believe... did not result in any compensable injury to you."
"...will not consider any payments with respect to your claim against OUR INSURED (my emphasis again) for injuries..."
For the record, they are in receipt of medical records verifying subjectively and objectively an injury thatis substantial enough to keep me off the flight deck. Obviously that information is being ignored. Besides, what does "physical condition at the time of the accident" mean anyway? An ambulance was not required at the time. Anyone with a modicum of medical knowledge, whch should include the adjustor, knows that an injury to the neck/back/head may take hours or even days to fully manifest itself. The freezeframe of the first few moments after an accident mean squat.
Likelihood of Lawyer involvement greatly increased as of now. I naively thought I was an insured as well with this entity. Lesson learned, lesson shared.
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flyinggirl
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Yikes....and all that money paid to icbc for a reply like that. bastards. Fight fight fight. My 75 year old nana did and she won! She swears by Klein Lyons now. Seriously. Its keeping you from working, thats huge. Not like you had an obvious broken toe or something, its a freakin' neck/head/back injury. Those injuries sometimes follow quite a bit later. Keep all documentation from the medical side of things and stop reading this now....you should be on the phone to a lawyer.
Love many, trust few, always tie on your own canoe
"Say no more ,say no more,know what i mean "said Palin
Flight deck eh loss of licence insurance ??Most airlines provide some degree of loss of licence insurance.
Be careful when you choose a lawyer as some of them are not Advocates for you. Some do a lot of settlements quickly to keep the cash flowing out of icbc.
This could turn into a clash of insurance companies. Perhaps your company insurance will go to bat for you
If the damage is permenant ICBC does have an excellent re-training rehabilitation education clause in the policy .150k per accident and no limits if you are not at fault (that may have changed read your policies)
Do not fear the insurance companies as the Judges are still in charge of Justice even in B.C. and they can spend a fortune on a dream team of lawyers .The Judges will do what is right get it in front of a Judge .
Flight deck eh loss of licence insurance ??Most airlines provide some degree of loss of licence insurance.
Be careful when you choose a lawyer as some of them are not Advocates for you. Some do a lot of settlements quickly to keep the cash flowing out of icbc.
This could turn into a clash of insurance companies. Perhaps your company insurance will go to bat for you
If the damage is permenant ICBC does have an excellent re-training rehabilitation education clause in the policy .150k per accident and no limits if you are not at fault (that may have changed read your policies)
Do not fear the insurance companies as the Judges are still in charge of Justice even in B.C. and they can spend a fortune on a dream team of lawyers .The Judges will do what is right get it in front of a Judge .
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RatherBeFlying
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If you are about to be rear-ended by a similar weight class vehicle, the best way to minimise injury is to stand on the brakes and be on a road with good friction -- likely not in your case if you were propelled 20 feet.
That's a heavy hit. I've been rear-ended at least twice, fortunately without lingering injury, but was NEVER pushed 20 feet.
Your injury factor is directly proportional to the acceleration imposed upon you.
Find a good lawyer -- be careful of asking your real estate lawyer to refer you to a personal injury lawyer as he may just send you to a good buddy.
Sometimes the newspapers will pick up a story like this and your insurer will suddenly "review" their decision.
That's a heavy hit. I've been rear-ended at least twice, fortunately without lingering injury, but was NEVER pushed 20 feet.
Your injury factor is directly proportional to the acceleration imposed upon you.
Find a good lawyer -- be careful of asking your real estate lawyer to refer you to a personal injury lawyer as he may just send you to a good buddy.
Sometimes the newspapers will pick up a story like this and your insurer will suddenly "review" their decision.
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BigWillyStyle
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The traffic analysts at the RCMP are crackerjack where I am. They know the math inside out. Any hospital reports and police reports in the hands of a good personal injury lawyer are solid gold.
BWS
BWS
I got out of aviation so I could afford a yacht big enough to pull up beside Doc's!
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cloudcounter
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Well, 'Jesus' would say :
Trust the Father and let ICBC carry it because they have the pockets.''
I was rearended in the bush once by a hot shot deadhead- eventually healed up but should have made a claim- young and dumb.
Your damages can really mount up - someone peeled my rear bumper and damaged side a bit this winter - about 3500 bucks 02 Suzuki
Good luck ,
cc
Trust the Father and let ICBC carry it because they have the pockets.''
I was rearended in the bush once by a hot shot deadhead- eventually healed up but should have made a claim- young and dumb.
Your damages can really mount up - someone peeled my rear bumper and damaged side a bit this winter - about 3500 bucks 02 Suzuki
Good luck ,
cc
Kilo-Kilo wrote:Don't say another word to the adjuster. Get a Lawyer.Captain S itmagnet wrote: The insurer is in fact ICBC.
Koran 5:33
The Punishment for those who oppose Allah and his messenger is : Execution or Crucifixion or the cutting off of ..snip
If Truth be not your goal,
you have achieved your gaol.
http://www.biblicalzionist.com/index.htm
The Punishment for those who oppose Allah and his messenger is : Execution or Crucifixion or the cutting off of ..snip
If Truth be not your goal,
you have achieved your gaol.
http://www.biblicalzionist.com/index.htm
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Conquest Driver
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Let's assume the above two statements, from previous posters, are correct.The moving vehicle weighs about 2500 pounds. The struck vehicle weighs about 4500 pounds.
GM has built thier vehicles with 5mph bumpers for years, meaning that there be no damage to the bumper itself beyond a 3/8 inch "dent" and 3/4 inch "set" (or displacement) from original position when impacted at 5mph.
As I understand it the 5 mph bumper applies to the struck vehicle (the 4500 pound one). In other words, you back the van into the proverbial "brick wall" at 5 mph and have no major damage.
Now we go to grade 12 physics (it's been a while).
f=1/2mv2
(force =half the mass times the velocity squared)
Using that formula you need a force of 56,250 something or others (I think it's Newtons or Slugs) to break the bumper. Or maybe it's Ergs or Dynes? Anyway it doesn't really matter.
So the attacking car must have generated this much force, right? But it only has a mass of 2500 pounds. So to generate a force of 56250 it has to have a velocity of 6.7 mph.
All of this assumes a pure "billiard ball on billiard ball" collision.
It assumes that the attacking car didn't absorb any of the shock whatsoever. That's nonsense. You'd have the front of that car crushing and acting as a fairly effective "shock absorber". To a lesser extent, so did your van. How much force does it take to bend the amount of metal that was bent, and crush the amount of fiberglass that was crushed; on both vehicles. Add that into the equation.
Only after all of this this do we get into the added force needed to overcome brake energy and road friction to move your vehicle 20 feet. Yet another number to add in.
So I think you can make a good case that he was well above 5 MPH.
Cheers
CD (who obviously has too much spare time)
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RatherBeFlying
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Vehicle Damage may have inverse correlation to personal injury in case of rear-ender victim.
As before said, if you were standing on the brakes and your tires and road surface kept your car from moving forward more than a foot, you would be subjected to minimal acceleration, but the cars would be seriously damaged.
In the case of a slippery surface, you are subjected to increased acceleration and injury potential, but this acceleration will minimise damage to the cars.
So ICBC in using a formula that denies injury below a minimum threshold of vehicle damage has got it bass ackwards.
As before said, if you were standing on the brakes and your tires and road surface kept your car from moving forward more than a foot, you would be subjected to minimal acceleration, but the cars would be seriously damaged.
In the case of a slippery surface, you are subjected to increased acceleration and injury potential, but this acceleration will minimise damage to the cars.
So ICBC in using a formula that denies injury below a minimum threshold of vehicle damage has got it bass ackwards.
Guys eliminate the variable you don't need! No need to do friction coeffiecients, degrees, etc.
We will assume that the vehicles didn't rotate appreciable so there is no rotational energy. Figure out how much the cas was deformed plastically (how big is the dent). Then figure out how far the car moved (20'). Use these number to determine how much energy was imparted on the car. Using this, you can determine the energy in the larger vehicle and thus the velocity at impact.
Shitmagnet, how many feet was you car deformed?
We will assume that the vehicles didn't rotate appreciable so there is no rotational energy. Figure out how much the cas was deformed plastically (how big is the dent). Then figure out how far the car moved (20'). Use these number to determine how much energy was imparted on the car. Using this, you can determine the energy in the larger vehicle and thus the velocity at impact.
Shitmagnet, how many feet was you car deformed?
This is not a question appropriate for "physics/math wizards". Anyone applying highschool or even university-level physics is making a lot of assumptions in their analysis of the problem, and their calculation will never stand up in court. You need to talk to an accident reconstruction engineer who does this professionally (no not just any engineer will do). These guys have lots of experience and have access to tons of empirical data that few other people do.
