Yes but not nearly as much as asphalt.
Jump out of a car going 60MPH and tell me what hurts more... the wind on your way down, or the asphalt once you hit it.
Yes but not nearly as much as asphalt.Originally posted by: pyonir
Isn't wind friction?
Originally posted by: Mutilator
Yes but not nearly as much as asphalt.Originally posted by: pyonir
Isn't wind friction?
Jump out of a car going 60MPH and tell me what hurts more... the wind on your way down, or the asphalt once you hit it.
Originally posted by: pyonir
Isn't wind friction?
Originally posted by: PlatinumGold
Originally posted by: conjur
Originally posted by: PlatinumGold
Originally posted by: ElFenix
actually thats impossible.when your tires lose contact with the pavement - your car will accelerate to a higher rate of speed
hmmm, let's see, what are the laws of thermodynamics with regards to objects in motion?
now what would happen to the object if the friction were removed?
yes, it is very possible.
The car doesn't increase its rate of speed...the tires increase their rate of spinning!
If there's little or no friction, just how the hell is the entire vehicle going to accelerate?
As a test, put your car on a lake of ice and floor it. Tell me what happens.
Yeah....thought so.
And, her car didn't take off like an airplane. It simply slid across a slick surface. I doubt she was traveling fast enough to actually go airborne like some NASCAR accident. Well, if she slid across a ditch or median and the car was launched into the air due to the slope of the ground, sure.
WRONG, we are not talking about starting from a standstill but from MOTION.
IN other words, you are traveling at 60 MPH, that means that there is a certain amount of inertia, there is a certain amount of kinetic energy because you are in motion. IF all friction is REMOVED, you will temporarily INCREASE your speed, NOT because of what your tires are doing but because your KINETIC energy is constant but FRICTION has been removed.
Originally posted by: conjur
Originally posted by: PlatinumGold
Originally posted by: conjur
Originally posted by: PlatinumGold
Originally posted by: ElFenix
actually thats impossible.when your tires lose contact with the pavement - your car will accelerate to a higher rate of speed
hmmm, let's see, what are the laws of thermodynamics with regards to objects in motion?
now what would happen to the object if the friction were removed?
yes, it is very possible.
The car doesn't increase its rate of speed...the tires increase their rate of spinning!
If there's little or no friction, just how the hell is the entire vehicle going to accelerate?
As a test, put your car on a lake of ice and floor it. Tell me what happens.
Yeah....thought so.
And, her car didn't take off like an airplane. It simply slid across a slick surface. I doubt she was traveling fast enough to actually go airborne like some NASCAR accident. Well, if she slid across a ditch or median and the car was launched into the air due to the slope of the ground, sure.
WRONG, we are not talking about starting from a standstill but from MOTION.
IN other words, you are traveling at 60 MPH, that means that there is a certain amount of inertia, there is a certain amount of kinetic energy because you are in motion. IF all friction is REMOVED, you will temporarily INCREASE your speed, NOT because of what your tires are doing but because your KINETIC energy is constant but FRICTION has been removed.
Ok, but all friction is NOT removed and you've removed the source of power to the driving wheels, too. Not all four tires are going to be completely frictionless.
And, a BIG thing everyone is overlooking is you are not going to a frictionless surface. Ever drive your car into a deep puddle and feel the steering wheel pull to one side? That's friction causing that one tire to essentially come to a complete stop and the other tire is still powered and is, in effect, steering the car around. Ever been in a pool and take your hand and skim it quickly across the surface to make a big rooster-tail looking splash? If it was frictionless, your hand would have no affect on the water, eh?
Originally posted by: PlatinumGold
Originally posted by: conjur
Originally posted by: PlatinumGold
Originally posted by: conjur
Originally posted by: PlatinumGold
Originally posted by: ElFenix
actually thats impossible.when your tires lose contact with the pavement - your car will accelerate to a higher rate of speed
hmmm, let's see, what are the laws of thermodynamics with regards to objects in motion?
now what would happen to the object if the friction were removed?
yes, it is very possible.
The car doesn't increase its rate of speed...the tires increase their rate of spinning!
If there's little or no friction, just how the hell is the entire vehicle going to accelerate?
As a test, put your car on a lake of ice and floor it. Tell me what happens.
Yeah....thought so.
And, her car didn't take off like an airplane. It simply slid across a slick surface. I doubt she was traveling fast enough to actually go airborne like some NASCAR accident. Well, if she slid across a ditch or median and the car was launched into the air due to the slope of the ground, sure.
WRONG, we are not talking about starting from a standstill but from MOTION.
IN other words, you are traveling at 60 MPH, that means that there is a certain amount of inertia, there is a certain amount of kinetic energy because you are in motion. IF all friction is REMOVED, you will temporarily INCREASE your speed, NOT because of what your tires are doing but because your KINETIC energy is constant but FRICTION has been removed.
Ok, but all friction is NOT removed and you've removed the source of power to the driving wheels, too. Not all four tires are going to be completely frictionless.
And, a BIG thing everyone is overlooking is you are not going to a frictionless surface. Ever drive your car into a deep puddle and feel the steering wheel pull to one side? That's friction causing that one tire to essentially come to a complete stop and the other tire is still powered and is, in effect, steering the car around. Ever been in a pool and take your hand and skim it quickly across the surface to make a big rooster-tail looking splash? If it was frictionless, your hand would have no affect on the water, eh?
of COURSE it's not frictionless. there is NO SUCH thing as a frictionless surface.
HOWEVER, there is a HUGE amount of friction removed. enough that one can safely say the car would actually ACCELERATE.
Remember it's an equilibrium.
A certain amount of energy to overcome TOTAL friction. ONCE you've achieved that speed, laws of thermodynamics say that you will maintain that speed until FRICTION slows you down.
INITIALLY you will have a certain amount of energy say 500 KiloJoules (numbers made up) the fact that your engine no longer supplies you with additional energy means, that friction will eventually slow you down BUT you have reduced your FRICTION significantly to the point where it is THEORETICALLY POSSIBLE to accelerate.
Originally posted by: conjur
Originally posted by: PlatinumGold
Originally posted by: conjur
Originally posted by: PlatinumGold
Originally posted by: conjur
Originally posted by: PlatinumGold
Originally posted by: ElFenix
actually thats impossible.when your tires lose contact with the pavement - your car will accelerate to a higher rate of speed
hmmm, let's see, what are the laws of thermodynamics with regards to objects in motion?
now what would happen to the object if the friction were removed?
yes, it is very possible.
The car doesn't increase its rate of speed...the tires increase their rate of spinning!
If there's little or no friction, just how the hell is the entire vehicle going to accelerate?
As a test, put your car on a lake of ice and floor it. Tell me what happens.
Yeah....thought so.
And, her car didn't take off like an airplane. It simply slid across a slick surface. I doubt she was traveling fast enough to actually go airborne like some NASCAR accident. Well, if she slid across a ditch or median and the car was launched into the air due to the slope of the ground, sure.
WRONG, we are not talking about starting from a standstill but from MOTION.
IN other words, you are traveling at 60 MPH, that means that there is a certain amount of inertia, there is a certain amount of kinetic energy because you are in motion. IF all friction is REMOVED, you will temporarily INCREASE your speed, NOT because of what your tires are doing but because your KINETIC energy is constant but FRICTION has been removed.
Ok, but all friction is NOT removed and you've removed the source of power to the driving wheels, too. Not all four tires are going to be completely frictionless.
And, a BIG thing everyone is overlooking is you are not going to a frictionless surface. Ever drive your car into a deep puddle and feel the steering wheel pull to one side? That's friction causing that one tire to essentially come to a complete stop and the other tire is still powered and is, in effect, steering the car around. Ever been in a pool and take your hand and skim it quickly across the surface to make a big rooster-tail looking splash? If it was frictionless, your hand would have no affect on the water, eh?
of COURSE it's not frictionless. there is NO SUCH thing as a frictionless surface.
HOWEVER, there is a HUGE amount of friction removed. enough that one can safely say the car would actually ACCELERATE.
Remember it's an equilibrium.
A certain amount of energy to overcome TOTAL friction. ONCE you've achieved that speed, laws of thermodynamics say that you will maintain that speed until FRICTION slows you down.
INITIALLY you will have a certain amount of energy say 500 KiloJoules (numbers made up) the fact that your engine no longer supplies you with additional energy means, that friction will eventually slow you down BUT you have reduced your FRICTION significantly to the point where it is THEORETICALLY POSSIBLE to accelerate.
That acceleration is going to be minimal and, in the grand scheme of things, a negligible effect to the rest of what's going on in that situation. The most dangerous aspect of that situation is the car is no longer going in a straight line, most likely. And, when it hits pavement again, it's going to throw the car into a spin or head it off into a ditch or something.
Well, I've had personal experience with hydroplaning on more than one occasion as well as hitting black ice while at speed. I can safely say there was no sudden burst of speed. I didn't have cruise control on (I'm not that stupid) and my car would just feel like it was floating. I didn't feel any acceleration and, in fact, in the case of hydroplaning, I could feel a bit of deceleration. And, the rocket effect when hitting dry pavement assumes the car is still pointed forward, which may not be the case.Originally posted by: PlatinumGold
Originally posted by: conjur
That acceleration is going to be minimal and, in the grand scheme of things, a negligible effect to the rest of what's going on in that situation. The most dangerous aspect of that situation is the car is no longer going in a straight line, most likely. And, when it hits pavement again, it's going to throw the car into a spin or head it off into a ditch or something.
Agreed and i never said otherwise. the statement was made "actually thats quite impossible". I was just saying that it is theoretically possible.
oh btw, i'm still not convinced that the acceleraltion will be negligible. in my opinion and i have no evidence to support this, it seems like there will be at least as much friction from the road as everything else combined, hence i think there will be significant acceleration.
HOWEVER, it isn't the most dangerous aspect of the situation.
also, there could be a rocket effect IF you hyroplane and then all of a sudden hit dry pavement as the CC will have increased your engines rpms significantly.
Originally posted by: geckojohn
pussycat13,
I do have a life, that's why i don't have time to read it. You just sit at your computer all day and read this = you don't have a life.
No speed sensors in the wheels. Cruise control works based on a combination of speed input either from a single undriven wheel or from the transmission output shaft, a set of vacuum monitors to read engine load, and the engine's RPM sensor, among other things.Originally posted by: se7enty7
A lot of people don't seem to know how cruise control works. It's not a "Stay at 30% power or 30% speed" type of thing.
It's a "stay at 60mph" kind of thing.
There are speed sensors in each wheel that do this.
Yes, for a very brief moment the car will be going faster, but not enough to "Make it fly like an airplane"
sounds to me like some girl doesn't know how to drive in the rain.
Also, you shouldn't have cc on while it's wet ANYWAY .. you need to be ready to stop, manuver, etc, which she very clearly didn't do
Exactly. The object would accelerate if the constant external force were still being applied to the object AFTER it hit the lower friction area; but in this case, the constant external force would be removed at the exact time the lower friction area is hit, therefore the only thing keeping the object in motion is inertia. If it gained speed it would violate the first law of thermodynamics.Originally posted by: bmd
PlatinumGold:
I think I'd have to disagree with you. Let's say you're pushing a block across a surface with friction, say cardboard for example. You push it at a constant speed, and maintaining that constant speed requires you to apply a certain force. Now to make the analogy to the hydroplaning example, let's say that the cardboard *instantly* turns to ice or some very very low friction surface, and at the same *instant* you stop pushing (the wheels cant power the car forward if they're slipping/hydroplaning). The block would not speed up just because it reached a lower friction surface. When pushing on cardboard, your pushing balances the friction, while on the ice there is essentially no friction, but also no pushing, so the speed would remain the same.
Also, for Kinetic Energy, it has some set amount of KE equal to 1/2 m*v^2. Now, if we keep the KE the exact same like you say, how is it supposed to accelerate? Does the mass decrease?
That said, I can see how the tires might spin more suddenly, although I'm not positive exactly how most CC systems work.
Originally posted by: Ophir
Exactly. The object would accelerate if the constant external force were still being applied to the object AFTER it hit the lower friction area; but in this case, the constant external force would be removed at the exact time the lower friction area is hit, therefore the only thing keeping the object in motion is inertia. If it gained speed it would violate the first law of thermodynamics.Originally posted by: bmd
PlatinumGold:
I think I'd have to disagree with you. Let's say you're pushing a block across a surface with friction, say cardboard for example. You push it at a constant speed, and maintaining that constant speed requires you to apply a certain force. Now to make the analogy to the hydroplaning example, let's say that the cardboard *instantly* turns to ice or some very very low friction surface, and at the same *instant* you stop pushing (the wheels cant power the car forward if they're slipping/hydroplaning). The block would not speed up just because it reached a lower friction surface. When pushing on cardboard, your pushing balances the friction, while on the ice there is essentially no friction, but also no pushing, so the speed would remain the same.
Also, for Kinetic Energy, it has some set amount of KE equal to 1/2 m*v^2. Now, if we keep the KE the exact same like you say, how is it supposed to accelerate? Does the mass decrease?
That said, I can see how the tires might spin more suddenly, although I'm not positive exactly how most CC systems work.
That's a completely separate case. It doesn't hit the ground directly over where it was dropped because of inertia, yes. But what does inertia do exactly? Inertia wants to keep something doing exactly what it's doing, and it won't change unless an external force is applied. So the bomb keeps the plane's forward velocity as it falls. Similarly, the car will keep it's initial forward velocity, and inertia will want the car to continue at the same speed. Inertia resists changes in an objects motion, it doesn't cause them.Originally posted by: PlatinumGold
Originally posted by: Ophir
Exactly. The object would accelerate if the constant external force were still being applied to the object AFTER it hit the lower friction area; but in this case, the constant external force would be removed at the exact time the lower friction area is hit, therefore the only thing keeping the object in motion is inertia. If it gained speed it would violate the first law of thermodynamics.Originally posted by: bmd
PlatinumGold:
I think I'd have to disagree with you. Let's say you're pushing a block across a surface with friction, say cardboard for example. You push it at a constant speed, and maintaining that constant speed requires you to apply a certain force. Now to make the analogy to the hydroplaning example, let's say that the cardboard *instantly* turns to ice or some very very low friction surface, and at the same *instant* you stop pushing (the wheels cant power the car forward if they're slipping/hydroplaning). The block would not speed up just because it reached a lower friction surface. When pushing on cardboard, your pushing balances the friction, while on the ice there is essentially no friction, but also no pushing, so the speed would remain the same.
Also, for Kinetic Energy, it has some set amount of KE equal to 1/2 m*v^2. Now, if we keep the KE the exact same like you say, how is it supposed to accelerate? Does the mass decrease?
That said, I can see how the tires might spin more suddenly, although I'm not positive exactly how most CC systems work.
IF you drop a bomb, where does it hit the ground? directly below the point at which it was dropped? Or directly below the point where the plane has traveled too?
you forget inertia is a lot, and given that inertia and the loss of friction the car would accelerate, even if it is only for a brief second.
Originally posted by: bmd
That's a completely separate case. It doesn't hit the ground directly over where it was dropped because of inertia, yes. But what does inertia do exactly? Inertia wants to keep something doing exactly what it's doing, and it won't change unless an external force is applied. So the bomb keeps the plane's forward velocity as it falls. Similarly, the car will keep it's initial forward velocity, and inertia will want the car to continue at the same speed. Inertia resists changes in an objects motion, it doesn't cause them.Originally posted by: PlatinumGold
Originally posted by: Ophir
Exactly. The object would accelerate if the constant external force were still being applied to the object AFTER it hit the lower friction area; but in this case, the constant external force would be removed at the exact time the lower friction area is hit, therefore the only thing keeping the object in motion is inertia. If it gained speed it would violate the first law of thermodynamics.Originally posted by: bmd
PlatinumGold:
I think I'd have to disagree with you. Let's say you're pushing a block across a surface with friction, say cardboard for example. You push it at a constant speed, and maintaining that constant speed requires you to apply a certain force. Now to make the analogy to the hydroplaning example, let's say that the cardboard *instantly* turns to ice or some very very low friction surface, and at the same *instant* you stop pushing (the wheels cant power the car forward if they're slipping/hydroplaning). The block would not speed up just because it reached a lower friction surface. When pushing on cardboard, your pushing balances the friction, while on the ice there is essentially no friction, but also no pushing, so the speed would remain the same.
Also, for Kinetic Energy, it has some set amount of KE equal to 1/2 m*v^2. Now, if we keep the KE the exact same like you say, how is it supposed to accelerate? Does the mass decrease?
That said, I can see how the tires might spin more suddenly, although I'm not positive exactly how most CC systems work.
IF you drop a bomb, where does it hit the ground? directly below the point at which it was dropped? Or directly below the point where the plane has traveled too?
you forget inertia is a lot, and given that inertia and the loss of friction the car would accelerate, even if it is only for a brief second.
You're talking about two very different things: Energies and Forces. KE = 1/2mv^2. Good. Now, in order for it to accelerate (v to increase) without changing the value of the kinetic energy, only 1 thing can happen: its mass must decrease. It's simple algebra. If mv^2=10, and you want v to increase, but the new mv^2 to still equal 10, m must go down. Obviously, this is not the case. The car's KE is constant. The car's mass is constant. Given those two, the velocity must also be constant.Originally posted by: PlatinumGold
Originally posted by: bmd
That's a completely separate case. It doesn't hit the ground directly over where it was dropped because of inertia, yes. But what does inertia do exactly? Inertia wants to keep something doing exactly what it's doing, and it won't change unless an external force is applied. So the bomb keeps the plane's forward velocity as it falls. Similarly, the car will keep it's initial forward velocity, and inertia will want the car to continue at the same speed. Inertia resists changes in an objects motion, it doesn't cause them.Originally posted by: PlatinumGold
Originally posted by: Ophir
Exactly. The object would accelerate if the constant external force were still being applied to the object AFTER it hit the lower friction area; but in this case, the constant external force would be removed at the exact time the lower friction area is hit, therefore the only thing keeping the object in motion is inertia. If it gained speed it would violate the first law of thermodynamics.Originally posted by: bmd
PlatinumGold:
I think I'd have to disagree with you. Let's say you're pushing a block across a surface with friction, say cardboard for example. You push it at a constant speed, and maintaining that constant speed requires you to apply a certain force. Now to make the analogy to the hydroplaning example, let's say that the cardboard *instantly* turns to ice or some very very low friction surface, and at the same *instant* you stop pushing (the wheels cant power the car forward if they're slipping/hydroplaning). The block would not speed up just because it reached a lower friction surface. When pushing on cardboard, your pushing balances the friction, while on the ice there is essentially no friction, but also no pushing, so the speed would remain the same.
Also, for Kinetic Energy, it has some set amount of KE equal to 1/2 m*v^2. Now, if we keep the KE the exact same like you say, how is it supposed to accelerate? Does the mass decrease?
That said, I can see how the tires might spin more suddenly, although I'm not positive exactly how most CC systems work.
IF you drop a bomb, where does it hit the ground? directly below the point at which it was dropped? Or directly below the point where the plane has traveled too?
you forget inertia is a lot, and given that inertia and the loss of friction the car would accelerate, even if it is only for a brief second.
there are differences between the bomb analogy and the car analogy obviously.
KE = 1/2mv^2
Once the car is free sliding, no external locomotion and very little friction to slow it down, it is kinetic energy, the instant it starts hydroplaning the amount of energy will exceed the amount of resistance so that it will accelerate. eventually the friction will overcome the KE and it will start to slow down.