calculating G's
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does anyone know off hand how to calculate the G of a car declelerating from 60 to 0 in 111 ft?

Had a quick search.

http://www.physicsforums.com/showthread.php?t=88098

Just looking at that equation made my brain leak out my nose.

1/4 Mile 14.3secs 96Mph Terminal 10psi of boost.


Fibreglass Parts? - http://www.tdkracing.co.uk/
Split Rims? - http://www.force-racing.co.uk/

I was staring at the wall dribbling.

done it! (i think)

60 Mph=27 metres per sec
111ft = 33.8 metres.
1G=9.812 mtres per sec per sec

dec in G= (starting velocity) squared over 2 x distance x 9.812

sooooo....

(-27) squared = 729

2x33.8x9.812= 663.29

729/663= 1.099G

Doesn't look too complicated!

I had a search through my old college work but then 2 years worth of work decided to jump out of the folder and onto the floor!

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1/4mile in 13.2sec @ 111 terminal on 15psi

argh its alive!!!

A level maths

v^2 = u^2 + (2 x a x s)

Where
v = Final Velocity
u = Initial Velocity
a = Acceleration
s = Distance

Rearranging

a = u^2/(2 x s)

Gives acceleration in units of ms^-2.

To get G's divide by 9.81

so

a = (27*27)/(2*33.8)

a = 10.784 ms^-2

Therefore g = 10.784/9.81 = 1.099 = exactly what you got above!

However that assumes a constant rate of acceleration throughout the braking period, which is almost definitely not the case, so the above is a bit of a simplification.

What about air resistance? :)

OK, ignoring that too.

In fact, fuck it, lets not forget to ignore the Vegard "Pedant Effect".

indeed that slows us all down, lol

cheers for confiming that Tom,

this was started by some one with a db9 claiming that they were pulling 3G under braking, I said i'd be supprised if it was much more than 1.5G

aston state their stopping distances as 11ft @60 and 327 ft@ 100 hence the above question.

dosent matter if its wrong, as long as it shuts him up! PMSL

looks complicated... I have a "G-Force Pro" gizmo, turn it on slam on the brakes and when the dust settles it tells ya!!

does cornering G's as well..

website:- http://www.terryhunt.co.uk

what sort of readings does that give for braking G?

As above the retardation won't be linear, maybe a peak of 3G is possible when the brake is first pressed and all the weight transfers to the front.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

I think even F1 cars only reach a max' of 3-4G. Perhaps m8y with the Aston has a RAF flight suit to keep the blood to the head?

Well a bit research suggest F1 cars have a maximum braking G of 4, so maybe 3 is a bit optimistic on road tyres.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

Indeed wil! lol

Would weight play a part too??? In the amount of G felt i mean.

1/4 Mile 14.3secs 96Mph Terminal 10psi of boost.


Fibreglass Parts? - http://www.tdkracing.co.uk/
Split Rims? - http://www.force-racing.co.uk/

This is what 4-5 (admittedly accelerative) Gs are like...

http://www.youtube.com/watch?v=Sbxguzogm1Q&feature=related

I believe your friend is comunicating through the wrong orifice.

Mental!

1/4 Mile 14.3secs 96Mph Terminal 10psi of boost.


Fibreglass Parts? - http://www.tdkracing.co.uk/
Split Rims? - http://www.force-racing.co.uk/

website:- http://www.terryhunt.co.uk

Thats when power/weight ratio kicks in. More weight needs more energy to obtain the same G's.

Edited by Jason G on 23rd May, 2008.

Yesterday i was following my friend into town. He was in his crx and i was in my kangoo. A bedford rascal got in between us and as we trundled along a road a 30mph I spotted a collection of hotties, looked infront and everyone had stopped.

My van pulled some serious G's!!!!!

The amusing thing was my friend did exactly the same as it was the car infront of him turning off

hahahahahaha

Hi,
Where they impressed with your kangaroo Nic?
Cheers,
Gavin :)

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