acceleration question (for techy type bods really)
#1
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the basic question is:
if you are accelerating from a standing start, disregarding the launch aspect, full pelt in 1st and second, if you lift off, does the car still accelerate?
and, if so, why?
the reaso i ask is because i have had a bit of an arguement with someone and i reckon that you would still be under the influence of the momentumt/inertia/forward motion of accelerating to not stop accelrating the absolute instant you dipped the clutch
does this make any sense?
and where can i find some proper evidence of this other than my eyes on the speedo
if you are accelerating from a standing start, disregarding the launch aspect, full pelt in 1st and second, if you lift off, does the car still accelerate?
and, if so, why?
the reaso i ask is because i have had a bit of an arguement with someone and i reckon that you would still be under the influence of the momentumt/inertia/forward motion of accelerating to not stop accelrating the absolute instant you dipped the clutch
does this make any sense?
and where can i find some proper evidence of this other than my eyes on the speedo
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#2
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you will still be accelerating as long as you engage clutch and lift of throttle at exactly the same time, if not you will be in engine braking once off throttle until the clutch is down. you defo are acelerating as ive looked at my speedo a few times when changing from 3rd to 4th and i engage clutch at 95 and its over 100 once im in 4th so im either still accelerating or my speedo cant keep up
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your rate of acceleration decreases but you still accellerate, but it gets slower and slower if you know what i mean... if you dipped your cluch and left it disengaged, you would slowly come to a standstill - i.e. decellerate...
#5
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V - U
---------
T
Once final velocity (or U) is reached then surely that's it, no more acceleration. As soon as you let off the max speed of that run or final velocity is reached so end of acceleration I'd say.
---------
T
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Once final velocity (or U) is reached then surely that's it, no more acceleration. As soon as you let off the max speed of that run or final velocity is reached so end of acceleration I'd say.
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![](https://i170.photobucket.com/albums/u247/n1lr3m/speedtimegraph.jpg)
that shows your speed 'vs' time.
the diagonal lines show your increasing speed as you accellerate, and the slopes show the accelleration decreases, but your speed doesnt get less, just the rate of speed.... im trying to explain it here... but im not too sure if you will understand it... hope this helps though!
#7
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Originally Posted by nilrem
your rate of acceleration decreases but you still accellerate, but it gets slower and slower if you know what i mean... if you dipped your cluch and left it disengaged, you would slowly come to a standstill - i.e. decellerate...
If you dip the clutch your car will not accelerate!
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#8
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Originally Posted by nilrem
![](https://i170.photobucket.com/albums/u247/n1lr3m/speedtimegraph.jpg)
that shows your speed 'vs' time.
the diagonal lines show your increasing speed as you accellerate, and the slopes show the accelleration decreases, but your speed doesnt get less, just the rate of speed.... im trying to explain it here... but im not too sure if you will understand it... hope this helps though!
You are totally and utterly mistaken.
Your speed will DROP when you disengage the clutch.
You will still cover distance, so maybe its distance not speed you are trying to talk about?????
#11
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Originally Posted by nilrem
your rate of acceleration decreases but you still accellerate, but it gets slower and slower if you know what i mean...
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Originally Posted by Chip-3Door
Originally Posted by nilrem
![](https://i170.photobucket.com/albums/u247/n1lr3m/speedtimegraph.jpg)
that shows your speed 'vs' time.
the diagonal lines show your increasing speed as you accellerate, and the slopes show the accelleration decreases, but your speed doesnt get less, just the rate of speed.... im trying to explain it here... but im not too sure if you will understand it... hope this helps though!
You are totally and utterly mistaken.
Your speed will DROP when you disengage the clutch.
You will still cover distance, so maybe its distance not speed you are trying to talk about?????
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#14
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Originally Posted by Chip-3Door
Originally Posted by GARETH T
no power,, no acceleration
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#15
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Originally Posted by scoooby slayer
if this is the case my speedo isnt keeping up with my acceleration then ![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
Same with a road angel etc
#17
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Originally Posted by nilrem
Originally Posted by Chip-3Door
Originally Posted by nilrem
![](https://i170.photobucket.com/albums/u247/n1lr3m/speedtimegraph.jpg)
that shows your speed 'vs' time.
the diagonal lines show your increasing speed as you accellerate, and the slopes show the accelleration decreases, but your speed doesnt get less, just the rate of speed.... im trying to explain it here... but im not too sure if you will understand it... hope this helps though!
You are totally and utterly mistaken.
Your speed will DROP when you disengage the clutch.
You will still cover distance, so maybe its distance not speed you are trying to talk about?????
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I understand fully what you are saying, its just that you happen to be totally and utterly completely wrong.
But you arent explaining it badly, PON misread what you said.
#18
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Took me a second to work that out as i was thinking that throwing something means no more power goes into it but it accelerates. Of course think about it for any longer than a second and you realise thats not true.
It will still be covering distance, perhaps at a decent rate, but it will bot increase in speed. As stated, it needs power to do that.
It will still be covering distance, perhaps at a decent rate, but it will bot increase in speed. As stated, it needs power to do that.
#20
Testing the future
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they say there's no such thing as a stupid question, only stupid answers - but this thread proves otherwise
some people didn't pay any attention in physics lessons
![Pthbbbb](https://passionford.com/forum/images/smilies/smile045.gif)
some people didn't pay any attention in physics lessons
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#21
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if you were to accellerate strongly(foot to floor) to 100mph and at 100mph dip the clutch, then you would still accelerate for a few seconds, but it would not be as fast, so you would probably ony get to 103/104mph, after this you would decellerate due to friction and wird resistanc, but you would still be accellerating and the rate of accelleration would be less until you decellerate... its not an on/off switch... you can have periods of no accelleration and no decelleration...
#22
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Originally Posted by nilrem
if you were to accellerate strongly(foot to floor) to 100mph and at 100mph dip the clutch, then you would still accelerate for a few seconds, but it would not be as fast, so you would probably ony get to 103/104mph, after this you would decellerate due to friction and wird resistanc, but you would still be accellerating and the rate of accelleration would be less until you decellerate... its not an on/off switch... you can have periods of no accelleration and no decelleration...
NO YOU FUCKING WELL WOULDNT
PLEASE STOP BREATHING AIR THAT COULD BE USED BY SOMEONE USEFUL
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Originally Posted by foreigneRS
they say there's no such thing as a stupid question, only stupid answers - but this thread proves otherwise
some people didn't pay any attention in physics lessons
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Pthbbbb](https://passionford.com/forum/images/smilies/smile045.gif)
some people didn't pay any attention in physics lessons
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
#25
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Surely once the clutch has been dipped the engine isn't transmitting power hence the car entering coast down? It won't be say for arguments sake, sitting at 70 then go up to 72 with the clutch engaged? Any idiot knows thats wrong.
#27
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i have to agree with chip i can not see how something can continue to accelerate. Maby you are thinking about going down a hill?
Also when you lift off the accelerator, there will still be fuel etc between the inlet and the pistons so maby that is the acceleration you are thinking about. or maby these cars that have electrics rather than cable for accel pedal. They may have a slight delay.
Also when you lift off the accelerator, there will still be fuel etc between the inlet and the pistons so maby that is the acceleration you are thinking about. or maby these cars that have electrics rather than cable for accel pedal. They may have a slight delay.
#28
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Originally Posted by Chip-3Door
Originally Posted by nilrem
if you were to accellerate strongly(foot to floor) to 100mph and at 100mph dip the clutch, then you would still accelerate for a few seconds, but it would not be as fast, so you would probably ony get to 103/104mph, after this you would decellerate due to friction and wird resistanc, but you would still be accellerating and the rate of accelleration would be less until you decellerate... its not an on/off switch... you can have periods of no accelleration and no decelleration...
NO YOU FUCKING WELL WOULDNT
PLEASE STOP BREATHING AIR THAT COULD BE USED BY SOMEONE USEFUL
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#29
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so, let me try and get this:
you gun it in first
you change gear
you gun it in second
you dip the clutch
are you still accelerating when you change from first to second between the changes and when the clutch is disengaged for that fraction of a second?
ie, is your speed still increasing because the momentum of the vehicle is causing the car to accelerate, even for a split second, after you have stopped sending power throgh the transmission?
theory and practical seem to show 2 different things
the theory is that with no power you wouldn't accelerate any more, although you may be able to coast at that sort of speed for some distance before the speed starts to drop off
but the practical seems to be that the speedo tends to keep going after you've lifted, so does this mean the speedo needle is continuing to move after you've stopped accelerating?
i'm still confused
i can understand it the other way, as soon as you take your foot of the brake pedal, you don't slow down as quickly, but is it the opposite the other way around like it should be?
you gun it in first
you change gear
you gun it in second
you dip the clutch
are you still accelerating when you change from first to second between the changes and when the clutch is disengaged for that fraction of a second?
ie, is your speed still increasing because the momentum of the vehicle is causing the car to accelerate, even for a split second, after you have stopped sending power throgh the transmission?
theory and practical seem to show 2 different things
the theory is that with no power you wouldn't accelerate any more, although you may be able to coast at that sort of speed for some distance before the speed starts to drop off
but the practical seems to be that the speedo tends to keep going after you've lifted, so does this mean the speedo needle is continuing to move after you've stopped accelerating?
i'm still confused
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i can understand it the other way, as soon as you take your foot of the brake pedal, you don't slow down as quickly, but is it the opposite the other way around like it should be?
#30
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Originally Posted by dojj
so, let me try and get this:
you gun it in first -
you change gear
you gun it in second
you dip the clutch
are you still accelerating when you change from first to second between the changes and when the clutch is disengaged for that fraction of a second?
ie, is your speed still increasing because the momentum of the vehicle is causing the car to accelerate, even for a split second, after you have stopped sending power throgh the transmission?
theory and practical seem to show 2 different things
the theory is that with no power you wouldn't accelerate any more, although you may be able to coast at that sort of speed for some distance before the speed starts to drop off
but the practical seems to be that the speedo tends to keep going after you've lifted, so does this mean the speedo needle is continuing to move after you've stopped accelerating?
i'm still confused
i can understand it the other way, as soon as you take your foot of the brake pedal, you don't slow down as quickly, but is it the opposite the other way around like it should be?
you gun it in first -
you change gear
you gun it in second
you dip the clutch
are you still accelerating when you change from first to second between the changes and when the clutch is disengaged for that fraction of a second?
ie, is your speed still increasing because the momentum of the vehicle is causing the car to accelerate, even for a split second, after you have stopped sending power throgh the transmission?
theory and practical seem to show 2 different things
the theory is that with no power you wouldn't accelerate any more, although you may be able to coast at that sort of speed for some distance before the speed starts to drop off
but the practical seems to be that the speedo tends to keep going after you've lifted, so does this mean the speedo needle is continuing to move after you've stopped accelerating?
i'm still confused
![Big Grin](https://passionford.com/forum/images/smilies/icon_mrgreen.gif)
i can understand it the other way, as soon as you take your foot of the brake pedal, you don't slow down as quickly, but is it the opposite the other way around like it should be?
momentum maintains speed, it does not raise it. All it affects is the rate of loos of speed due to resistive effects
The speedo is a big pile of wank and not to be believed, neither incidentally is gps, as it has a slo refresh rate and relies on doing the same thing for a period of time for accuracy.
Did no one else do o level physics?
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#31
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Originally Posted by nilrem
Originally Posted by foreigneRS
they say there's no such thing as a stupid question, only stupid answers - but this thread proves otherwise
some people didn't pay any attention in physics lessons
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Pthbbbb](https://passionford.com/forum/images/smilies/smile045.gif)
some people didn't pay any attention in physics lessons
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
F = MA
Therefore A = F/M
If you cant understand that, PLEASE stop commenting on this thread and giving DOJJ false hope he isnt totally wrong like always.
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Just scanned thru not reading properly
But did anyone mention the ground you on
ie if you was travelling down hill you could keep accellerating but if you was going uphill you would start decellerating, if on a level ground then you would be slowing, slowly but slowing wether foot on or off clutch, with foot on you would be naturaly decellerating, with foot off you would actually be braking.
my view anyway lol
Steve
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But did anyone mention the ground you on
![Wink](https://passionford.com/forum/images/smilies/icon_wink.gif)
ie if you was travelling down hill you could keep accellerating but if you was going uphill you would start decellerating, if on a level ground then you would be slowing, slowly but slowing wether foot on or off clutch, with foot on you would be naturaly decellerating, with foot off you would actually be braking.
my view anyway lol
Steve
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Originally Posted by GARETH T
heres one,,,,
if you hit a fly when doing 100mph, does it make the car stop?![Big Grin](https://passionford.com/forum/images/smilies/icon_mrgreen.gif)
if you hit a fly when doing 100mph, does it make the car stop?
![Big Grin](https://passionford.com/forum/images/smilies/icon_mrgreen.gif)
BUT, if you consider momentum, all you do is sum the momentum of the two objects, so;
MassCar x VelocityCar - MassFly x VelocityFly = post impact momentum.
Then divide the new momentum by the mass of the car, and you see how much the car actually slowed down.
Mart
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Originally Posted by Chip-3Door
Originally Posted by nilrem
Originally Posted by foreigneRS
they say there's no such thing as a stupid question, only stupid answers - but this thread proves otherwise
some people didn't pay any attention in physics lessons
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Pthbbbb](https://passionford.com/forum/images/smilies/smile045.gif)
some people didn't pay any attention in physics lessons
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
F = MA
Therefore A = F/M
If you cant understand that, PLEASE stop commenting on this thread and giving DOJJ false hope he isnt totally wrong like always.
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
#38
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Originally Posted by ECOS95
Originally Posted by Chip-3Door
Originally Posted by nilrem
Originally Posted by foreigneRS
they say there's no such thing as a stupid question, only stupid answers - but this thread proves otherwise
some people didn't pay any attention in physics lessons
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Pthbbbb](https://passionford.com/forum/images/smilies/smile045.gif)
some people didn't pay any attention in physics lessons
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
F = MA
Therefore A = F/M
If you cant understand that, PLEASE stop commenting on this thread and giving DOJJ false hope he isnt totally wrong like always.
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
![Surprised](https://passionford.com/forum/images/smilies/bigcry.gif)
from what i was taught if you throw a ball, the second the ball leaves your thrust, theoretically there it should decellerate, but in reality there is a fraction of a second where the friction has not overcome the accelleration proficiently enough to affect the speed in a negative effect, so essentially it is still accellerating...
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if you throw a ball up as soon as it leaves your hand it is decelerating instantly, without any force how could it accelerate, they only acceleration acting on it will be mg (gravity) in the opposite direction.
basically with no force applied an object cannot accelerate.
basically with no force applied an object cannot accelerate.