gizZzmo

Need help with a physics related question.

FYI, got smoked the other day at an intersection, traffic lights were out, other driver did not treat as 4-way stop. Trying to present a strong case to insurance since they most likely will try to pin 50/50 fault b/c of malfunctioning lights/lack of witnesses/no red light cameras = my word vs. his.

Here's the problem:

Take a car that can do 0-60mph in 7.7 seconds (96,500 meters/sec)...

What speed would the car be traveling at, at a distance of 30 meters (from a dead stop)??

Let me know if you need more info. I've tried figuring this out and have a rough idea, but would like to double check my findings.

Much appreciated.

miss_jess

iTrader: (2)

25-30km/h


and if its his word vs yours.... what did he say? Did you file a police report? Did you call the police to the scene? Since you said you were 'smoked' at an intersection, it sounds bad. Hopefully you are ok.

MPR

Might want to check that number 96,500 meters per second is FAST! lol.

Just make a good guess at the speed.

Polkaroo Killa

Ha ha ha......it's ludicrous speed!

gizZzmo

I called cops, they refused to file a report on scene...referred me to collision reporting center. I don't know what he said, english was not the best. I imagine he put something deferring him from fault. Luckily everyone was O.K.

Woops, that was supposed to be 96,500 meters/hour.. NOT / second.

60mph = 96.5 kmh
96.5 kmh = 96500 meters/hour
=26.8 metres / second

@ miss_jess, how did you arrive at 25-30km/h??

Thanks

orthow

Your calculation won't work as it is based on the assumption that the other car was accelerating under WOT.. 99.9% of the time this is not the case with cars driving on the road.

gizZzmo

I understand that, Im aware that the driver was most likely not accelerating under WOT, however It can still help me prove a point: that if the driver was going approx 60 kmh at the time of impact (which he certainly was), he could not possibly have come to a dead stop only 30 meters before, because under WOT it would have taken him X amount of meters (>30) to reach his impact speed 60 km/h = therefore he failed to stop at the intersection.

MPR

...Or just say "he didn't stop at the intersection". Which, by what you tell us, is what happened.

1999blksi

60mph=100km/h
As you mentioned ~ 26m/second....so to travel 30m we will say it took him 1.1 seconds.

if he can do 100km/h in 7.7seconds, that means 100/7.7= speed per second

Answer: He was going APPROXIMATELY 13km/h.

gizZzmo

lol. Ya, I obviously said that. Granted if you know anything about insurance companies they don't just take your word at face value. How many people do you think try and flip the story around when speaking to their insurance company? That's why I'm after something more tangible, more concrete. The damages in this case, do not lie.

him



me

gizZzmo

EXACTLY. pretty much bang on with what i got (8.72 miles or 14 kph). Now... is 14 kph likely to do something like this? Definitely not. Meaning he did not stop



ME



HIM

D.T.P

Acceleration is a curve of change of speed. Every second causes the car to accelerate, not always the same due to different gearing. First of all you need the force, weight and mechanical advantage ratio (gear ratio).
You cannot just take the time it took to accelerate 0-60mph and use the information. Now if you had something to compare it with you could make a guestimation which again wouldn't be exact due to mechanical advantage.
I would say maybe 25-30km/h but that's just a guess. Again do not underestimate speeds like 30km/h. If the driver didn't brake or was even braking and impact occured at 30km/h that still does a LOT of damage.
Your best bet would be find a video on youtube of somebody doing 0-x km/h and count second for let's say 0-50km/h. So then atleast you have a comparison and rate of acceleration. And no, diving the 0-100km/h by 2 will NOT give you an accurate answer.
GL but you will never find an accurate answer unless you find out all the unknowns I mentioned above.

1999blksi

25-30km/h would be inaccurate but explain how you go that speed pls

miss_jess

iTrader: (2)

how did you not get any witnesses in a busy intersection like that?!

gizZzmo

if I only knew.... nobody wanted to come forward

rick10

that sucks ! ... I m guessin this will be a writte off. Then again did you have full coverage insurance ?..

miss_jess

iTrader: (2)

ohhhh man.. I'm sorry to hear that. I would have like pulled someone out of a car and demanded them be my witness!

its probably going to be declared 50/50 by your insurance company. You will have to pay half your collision deductible and you will have an at fault accident on your record..

gizZzmo

- collision. Meaning unless insurance deems 100 not at fault, i lose big time

miss_jess

iTrader: (2)

well.. if insurance deems you not at fault, you don't pay any deductible and you will overall be fine

but yes, an at fault collision claim will affect your insurance unfortuntely

rick10

I think he meant that his insurance is collision only or one way. Meaning if it is 50/50 he does not get a new car or his car fix.

I may be wrong by he meant but if i m right then it damn sucks. Fight it until the end