knight:
Surely the impact of a car hitting a wall would be less than than a head on collision with two cars. The wall has no kinetic energy where both cars would have, assuming the speeds add up to the same.
The wall not having kinetic energy is irrevelant.
Two cars @ 45 hitting head on, or 20 & 70 or 30 & 60 still gives a impact speed of 90mph. The fact that there are TWO cars though might add extra “crumple factor” which cushions some of the blow, compared to merely hitting a brick wall with a single car at 90mph - the brick wall being stationary
(although police have been known to speed-gun brick walls moving at considerable speed! )
If you drove into a one tonne marshmallow at 90mph you will probably survive. Hit a brick wall at the same speed, and you probably won’t.
Neither would I expect the same result of impact from a Datsun Cherry driving into a Fiat 126 over a Bentley driving into a Volvo…
This is INERTIA rather than “zero kinetic energy” then. Something heavy that won’t be moved from it’s current position very easily could be said to have inertia that forces whatever hits it at 90mph to stop in a very short space indeed.
Everyone knows it’s the stopping that kills you - not the speed.
knight:
Surely the impact of a car hitting a wall would be less than than a head on collision with two cars. The wall has no kinetic energy where both cars would have, assuming the speeds add up to the same.
The wall not having kinetic energy is irrevelant.
Two cars @ 45 hitting head on, or 20 & 70 or 30 & 60 still gives a impact speed of 90mph. The fact that there are TWO cars though might add extra “crumple factor” which cushions some of the blow, compared to merely hitting a brick wall with a single car at 90mph - the brick wall being stationary
(although police have been known to speed-gun brick walls moving at considerable speed! )
If you drove into a one tonne marshmallow at 90mph you will probably survive. Hit a brick wall at the same speed, and you probably won’t.
Neither would I expect the same result of impact from a Datsun Cherry driving into a Fiat 126 over a Bentley driving into a Volvo…
This is INERTIA rather than “zero kinetic energy” then. Something heavy that won’t be moved from it’s current position very easily could be said to have inertia that forces whatever hits it at 90mph to stop in a very short space indeed.
Everyone knows it’s the stopping that kills you - not the speed.
The two crumple zones v just one in the case of a equivalent combined speed 90 mph head on crash v one in the case of hitting a brick wall at the same speed would be irrelevant at the types of speed in question.IE the excess energy is far greater than either one or two crumple zones can deal with.However just like the wall wins the equation might work out in the case of a smaller/weaker car acting as the whole crumple zone in favour of the stronger one or at least in which the shortest crumple zone loses to the longest in the case of a 90 mph combined speed head on crash between the Cherry v the Bentley,or for that matter a cab over truck v a conventional for example.IE any chance of survival depends on being able to get rid of the energy over as long a distance and time as possible while keeping the vehicle intact enough to protect it’s occupants.Which at 90 mph is always going to be a tall order but which probably explains maternal instincts resulting in the big 4x4 arms race for the local school run.
I watched that mythbuster episode and I’m pretty sure that two cars having a head on at 60mph was the same as hitting a wall at 60, it wasn’t multiplied.
I don’t know how it works with different impact speeds, but I assume that one doing 40mph and the other doing 60mph would be the same as hitting a stationary object at 50mph.
The combined impact speed is shared between the two vehicles, but then the effectiveness of crumple zones and the mass of the two vehicles would have to be identical.
In respect of the OP, the speed may have been a factor, something travelling at approx 100mph could hit you as you pull out, whereas something travelling slower may be able to take avoiding action. Without the facts though, that’s just a guess…
And he is right.Knowing where ,when and how to use speed on a bike is crucial,
If your on a bike at speed you are aware or you are going to die.
Everybody should have to learn to drive a motorcycle at “lunatic” speeds.
120 or 130 mph and develope the.what would you call it,
Survival skills that some jerk in a car or truck never develops.
On a bike I drive like a ■■■■ but I drive like every buggers out to kill me
They did an experiment showing that if you hit an immovable object at a speed. Then collide to objects with that same speed, the the two objects would sustain significantly less damage than the singular one.
This was because every action has an equal and opposite. The small experiment used plasticine before they scaled it up and used full sized cars.
I do agree with whoever said, “it’s the stopping though”
newmercman:
I watched that mythbuster episode and I’m pretty sure that two cars having a head on at 60mph was the same as hitting a wall at 60, it wasn’t multiplied.
I don’t know how it works with different impact speeds, but I assume that one doing 40mph and the other doing 60mph would be the same as hitting a stationary object at 50mph.
Imagine that two trucks are running on a changeover trunk run heading towards each other at 60 mph in each opposite direction.From the point of view of time and speed from either truck they are heading towards each other at a combined speed of 120 mph not 60 mph.The same applies in the event of the energy involved in them meeting head on.The energy ( and damage ) of the resulting crash will be 120 mph worth from the point of view of either vehicle.Or to put it another way the same damage that ‘both’ of them would have suffered if ‘either’ of them had run into the other head on at 120 mph while one of them was stationary.
No, because at the point of impact both lorries will stop instantly, so it will be like hitting a solid non deformable object at 60mph, rather than hitting another stationary lorry at 60mph, which will absorb some of the energy.
So you are right, but also wrong, it’s the difference between a hitting a solid object or something deformable that causes the confusion.
newmercman:
No, because at the point of impact both lorries will stop instantly, so it will be like hitting a solid non deformable object at 60mph, rather than hitting another stationary lorry at 60mph, which will absorb some of the energy.
So you are right, but also wrong, it’s the difference between a hitting a solid object or something deformable that causes the confusion.
I think…
You’re right the more solid more non deformable object scenario is a red herring which creates some confusion.However we’ve already established that the comparison in this case is a like with like car v car or truck v truck head on collision.In which case their deformation abilities don’t alter.IE they’ve both driven into each other both travelling in opposite directions at 60 mph and although it might ‘seem’ like they stop ‘instantly’ they’ve both still got to get rid of 120 mph worth of energy in the form of damage to both vehicles before they stop.It’s then just a matter of increasing the odds by who’s got the strongest vehicle with the most distance between the point of impact and where the driver is sitting.I’ll take the conventional and you can take the cab over.
Without knowing the type of road or indeed particulars of the accident it’s hard to comment.
But if this is a case of a car turning across a motorbike travelling at speed, at 97 mph, the motorcycle would be closing at 43 metres per second.
lets suppose a motorist of reasonable intelligence would not usually foresee a motorcycle travelling at that speed and probably assumed it was travelling at the posted speed limit (we’ll assume 60mph). Suppose the maneuver the car was performing would take around 4 seconds to be clear of presenting a hazard to oncoming traffic, at 60 mph the motorcycle would have closed down the car at 27 metres per second and would have traveled 135 metres. at 97 mph it would close at 43 m/s and traveled nearly twice that distance at 258 metres.
I would assume the car driver would not have reasonably been expected to presume the bike would be hurtling towards them at 97mph and (perhaps wrongly) miscalculated the bike’s speed and assumed they had enough time to complete their manoeuver and that the district judge is a complete arse.
waddy640:
According to a District Judge hearing a case of causing death by careless driving, the fact that the victim, a motorcyclist, was travelling at 97mph at the point of impact was not relevant. It was solely the actions of the car driver.
How about a link to the story so we can decide for ourselves whether the judge was right or wrong.
How about if the person who was traveling at 97mph hadn’t been, they would’ve arrived on the scene later thereby avoiding said other vehicle and hey presto! No accident - speed is ALWAYS a factor.
My pal was killed when a car pulled out of a junction on him. He only knew one speed…flat out. The poor car driver had no chance of seeing him approach at well over ton on a country road. Of course speed is a factor. These are public roads for all of us to use, and I speak as a lifelong motorcyclist.
alamcculloch:
I see this as a miscarriage of justice ,the motor cyclist was breaking the law by exceeding the set speed limit.
So if you pulled out into the path of another motorist and they were doing 31 in a 30 area does that exonerate you from any blame? The answer would be no (and rightly so)
The problem with “pleading guilty” is that it takes advantage of someone feeling bad after an accident that may well have not been their fault.
Once the guilty plea is in, they can have all kinds of other accusations thrown at them.
Best to let a Jury find you guilty of something, and leave it to them as to what exactly.
I wouldn’t want to get a 2 year ban from driving and a £1200 fine because some idiot jumped off a bridge under the truck wheels - like happened to someone I knew.
Q: Are you guilty or not guilty of running over that person prone on the ground?
A: Guilty.
Doh!
Doya think he was hard done by? He could even have argued that he ran over a carcass, and not a living person who wanted to stay alive at all!
Winseer:
The problem with “pleading guilty” is that it takes advantage of someone feeling bad after an accident that may well have not been their fault.
Once the guilty plea is in, they can have all kinds of other accusations thrown at them.
Best to let a Jury find you guilty of something, and leave it to them as to what exactly.
I wouldn’t want to get a 2 year ban from driving and a £1200 fine because some idiot jumped off a bridge under the truck wheels - like happened to someone I knew.
Q: Are you guilty or not guilty of running over that person prone on the ground?
A: Guilty.
Doh!
Doya think he was hard done by? He could even have argued that he ran over a carcass, and not a living person who wanted to stay alive at all!
Utter tosh!
It’s often months after being charged that one goes to court to enter a plea. As far as I’m aware there is no actual offence of which you state above, the accused would be asked to enter a plea for causing death by dangerous driving which going by the circs as you describe would;
a) warrant a not guilty plea
b) fall outside the 51% chance of a conviction and so would be dropped by the CPS before trial
If the speed at point of impact was 97mph, then
1 the bike was travelling much faster than this and braked, or
2 the bike was travelling at 97 and the car pulled out straight in front giving no time to brake.
assuming that 1 was the case, how fast must he have been going to emergency brake and still be doing 97?
I stand by my original post.Having looked at the picture the crash happened in a suburban area with kerbs and other road furniture.What is the speed limit at the location.I once emerged out of a farm road end and had a bike scream past me before I had straightened the bus up.He was not in sight when I committed to driving out.I or any of you could so easily be in this motorists position.Its a criminal offence to exceed 60 mph on a single carriageway.
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