Engineer Garin's Paraboloid - page 19
You are missing trading opportunities:
- Free trading apps
- Over 8,000 signals for copying
- Economic news for exploring financial markets
Registration
Log in
You agree to website policy and terms of use
If you do not have an account, please register
Yes of course it's a flub: read the thread - for some reason the existence of unprofitable locks has been linked to the existence of forces of inertia, or rather centrifugal force.... There is nothing to discuss on the subject .....
There was no suggestion about the presence or absence of such a connection. There was only the thesis that there is no such thing as: a) profitable or unprofitable lots; b) centrifugal force.
Let me tell you a terrible secret: there is no such thing as inertia, either - I mean, there is no such thing at all:) If the accelerator presses you into the seat, it does not mean that the accelerator somehow magically causes some force acting on your flesh.
There is a cause and there is a consequence. Acceleration is the consequence and the cause is the force, not the other way around.
Tara was running around complaining that he had suffered the fate of Sharikov (his login was stolen). Ask him about it.
tara: Just been as Sharikov :) What's going on with the forum... Changed the password, just in case. Sharikov, I recommend you too.
Vladislav, the post about Euclidean logic and theoretical mechanics was mine :) Sharikov, please don't delete it :(
There was no suggestion of the existence or non-existence of such a link. There was only the thesis that there is no such thing as a) profitable or unprofitable locks and b) centrifugal force.
Let me tell you a terrible secret: there is no such thing as inertia, either - I mean, there is no such thing at all:) If the accelerator presses you into the seat, it does not mean that the accelerator somehow magically causes some force acting on your flesh.
There is a cause and there is a consequence. Acceleration is the consequence and the cause is the force, not the other way around.
As for the assumptions about locks: yes it is clear - you took the joke too seriously.
And what about forces of inertia, ok they are not - let's move from controversial statements to concrete actions: please draw or describe the system of forces acting on your car in a turn and explain their nature and effect of car rollover, and similarly about getting oil ... I hope you won't claim that oil doesn't exist or that the car doesn't tilt in a corner ? - Now it's your turn. Waiting.
By the way, such branch of mechanics, as the Theory of mechanical fluctuations is constructed on presence of forces of inertia and it I yet about dynamics of mechanical systems did not recollect and the VAT (the stress-strain state) of mechanical dynamic systems. In general in mechanics there is sheer obscurantism, according to your words ))))))))) ... except that bridges are calculated, planes fly... horror ......
As for the assumptions about lokas: yes, it's clear - you took the joke too seriously.
And about forces of inertia, ok there are none - let's pass from disputable statements to concrete actions: please draw or describe system of forces acting on the car in a turn and explain their nature and effect of tilting of the car, and similarly about reception of oil ... I hope you won't claim that oil doesn't exist or that the car doesn't tilt in a corner ? - Now it's your turn. Waiting.
By the way, such section of mechanics as the Theory of mechanical fluctuations is constructed on presence of forces of inertia and it I yet about dynamics of mechanical systems have not recollected and the VAT (the stressed-strained condition) mechanical dynamic systems. In general in mechanics there is sheer obscurantism, according to your words ))))))))) ... except that bridges are calculated, planes fly... horror simply ......
1. The centrifugal force is a false force, the idea of which is based on a misunderstanding of the complex relationship between the action characterizing the force and the object of application of that force. (remembered from school).
2. When you turn a car's steering wheel, the normal component of the thrust (centripetal force) applied to the steering wheels at their grip points appears. This causes the points to move towards the centre of the curve whereas the centre of mass, to which no force is applied, continues in a straight line. The leverage is created when the centre of mass is above the road - the internal (relative to the curve) side of the vehicle rises and a normal component (centripetal force) arises which is already applied to the centre of mass - the vehicle moves into the turn under the effect of this force.
3. Special applications can use all sorts of aggregates, derived concepts, etc. For example, an operation mode of centrifuge is characterized by overloading A=G/g, the effect of which is equivalent to weighting contents of centrifuge by A times. It is equivalent, but by no means identical, because it is not the passenger in centrifuge seat that presses on backrest with centrifugal force F=m*G, but backrest presses on passenger with corresponding centripetal force.
1. Centrifugal force is a false force based on a misunderstanding of the complex relationship between the force and the object of application of that force. (remembered from school)
2. As the vehicle turns the steering wheel, a normal component of the traction (centripetal force) is applied to the steering wheels at their grip points. This causes the points to move towards the centre of the curve whereas the centre of mass, to which no force is applied, continues in a straight line. The leverage is created when the centre of mass is above the road - the internal (relative to the curve) side of the vehicle rises and a normal component (centripetal force) arises which is already applied to the centre of mass - the vehicle moves into the turn under the effect of this force.
3. Special applications can use all sorts of aggregates, derived concepts, etc. For example, an operation mode of centrifuge is characterized by overloading A=G/g, the effect of which is equivalent to weighting contents of centrifuge by A times. It is equivalent but by no means identical because it is not a passenger in centrifuge chair that presses on backrest with centrifugal force F=m*G, but backrest presses on passenger with corresponding centripetal force.
1. in the first classes of school, they used to say that negative numbers do not exist and that according to Archimedes' law, the force is applied to the centre of mass - there are a lot of simplifications and postulates at school that are changed and specified later on.
2. I did not ask why the car enters a turn - of course under the influence of the driving force, let it be traction force - but why it tilts and not in the direction of the turn. Since the pivot point (not the turn, but the tipping point), is in the contact patch, the centripetal force, which is in the same plane, can in no way create a tipping moment: the centripetal force is directed inside the turn, and the tipping goes in the opposite direction and the pivot point is the contact patch where this force, centripetal, is applied, the lever is zero there and cannot create a moment relative to the pivot point. If the pivot point were around the centre of mass, there would be no question about the need to introduce inertial forces ;).
Yes, and under the action of centripetal force, without compensation by any other forces, which in mechanics are called forces of inertia, and in your opinion do not exist, the passenger should move towards the centre of turn, that is in the direction of force action, but he does not want to, that is the problem ;). What to do about it?
Also, how does a centripetal force directed towards the centre create stresses in a sling rope, for example? These are all vector quantities that act along the direction of the applied forces. The centripetal force should produce compressive stresses in the rope. You can take your word for it or study resilience and elasticity theory - tensile stresses are created. I specifically cited the example of a rope - there can be no compressive stress in it: it has no compression resistance, only tensile resistance.
1. yes, and in the first years of school they used to say that negative numbers do not exist and that according to Archimedes' law, the force is applied to the centre of mass - there are many simplifications and postulates in school, which are changed and clarified later on.
2. I did not ask why the car enters a turn - of course under the influence of the driving force, let it be traction force - but why it tilts and not to the side of the turn. Since the pivot point (not the turn, but the tipping point), is in the contact patch, the centripetal force, which is in the same plane, can in no way create a tipping moment: the centripetal force is directed inside the turn, and the tipping goes in the opposite direction and the pivot point is the contact patch where this force, centripetal, is applied, the lever is zero there and cannot create a moment relative to the pivot point. If the pivot point were around the centre of mass, there would be no question about the need to introduce inertial forces ;).
Yes, and under the influence of centripetal force, without compensation, the passenger should move towards the centre of turn, that is in the direction of force, but he does not want it, what a pity ;).
Also, tell me how centripetal force directed to the centre creates tensions in a sling rope, for example? These are all vector quantities that act along the direction of the applied forces. The centripetal force should produce compressive stresses in the rope. You can take your word for it or study resilience and elasticity theory - tensile stresses are created. I specifically cited the example of the rope - it cannot produce compressive stresses: it has no resistance in compression, only tension.
I wrote a few pages ago - all the forces you, Vladislav, write about exist exclusively in non-inertial reference systems associated with the observer. They are introduced FICTIVELY in order that in these non inertial systems Newton's 2 law is formally fulfilled. These forces are not required to describe motion in any inertial system.
Specially for you a picture
A body (let's say a car), moving at constant modulo velocity around a circle, has a frictional force, which tends to pull it off the rectilinear trajectory. Since no force _does NOT oppose it, it succeeds: the velocity vector V0 is changed by the vector V1 - it is the same in modulo, but not in direction!!!!! The difference of these vectors (remember the rule of the triangle) is the vector dV, which is directed towards the centre of the circle. If we divide it by the elapsed time (scalar), we get the acceleration vector pointing naturally in the same direction. In the picture, directions dV and Ftr do not coincide a bit, as a rather long segment of time is chosen to make it clear. In the 8th grade kinematics course, it is proved that in the limit (at dt tending to 0), the acceleration vector will be exactly directed to the centre of the circle.
Newton's 2nd law of motion in the frame of reference Earth:
Ftr = m*dv/dt
If you introduce here some force, which supposedly should balance the friction force, then where does the acceleration come from? (By the way, note - the topic in the above-mentioned physics textbook for 8th grade is called "Acceleration in uniform motion on a circle". My picture is taken from there as well).
But if to pass to non-inertial system, connected with a car (in which it, naturally, is at rest), the acceleration suddenly disappears, therefore it is necessary to introduce centrifugal force to balance force of friction, I repeat, with a unique purpose - to achieve formal fulfillment of Newton's law. But it is possible to do it, because the principle of relativity in this case is not an edict for us - it means the invariance of the laws of nature only in inertial systems of readout.
With forces of inertia the picture is even more simple.
So don't fool people's brains. Even if you have been engaged in mechanics for a long time, it is useful to reread the basics sometimes.
And here is the rollover
As you can see, the friction force has torque and without any centrifugal force, therefore it can tip the car (and does so, and in exactly the same direction as drawn). The introduction of centrifugal force in a non-inertial system will have no effect on the result, since it will, as rightly pointed out, be applied exactly to the centre of mass, and will not create any torque.
Guys, I won't finish this thread right away... I'm tired.
If anyone is interested, I wrote the algorithm of the root post into the Expert Advisor... if anyone is interested I can sell it:)
I have to tell you right away... the tester showed positive results only on a "limited area" and a 30 min chart on this algorithm
Look for the grail elsewhere:)
Just in case, lest I be called a schoolboy and accused of being addicted to 8th grade textbooks)))
Butikov E.I., Bykov A.L., Kondratyev A.S. Physics for entering universities. 2nd ed. 1982. 610 pp.