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If you view the disks as separate bodies, then you are right: F1 is not the only force on disk 1; the rod itself is exerting a torque on the disk. Same goes for disk 2.firavia said:my question is:
if we take disk2 alone , we obviousely see that it is rotating with constant angular velocity so the angular accelration is 0 , but the confusion is , how can we have an angular accelration = to 0 if we have 1 tangential force on disk2 , isn't it impossible cause we know sum of torques = 0 , and if we have 1 force that casue 1 torque then the sum of torques would be not eqaul to zero but in the same time we see that the disk2 is rotating with constant angular velocity , it is impossible we got to have another force on disk2 to make an equilibrium of torques.
If the torque exerted on the system about the given axis by F1 is equal an opposite to the torque exerted by F2, then the net torque on the system is zero. The connecting rod links the two disks. (You don't really have to worry about the forces exerted by the rod on the disks as those forces are internal to the system and thus in themselves exert no net torque on the system. But they certainly do act!)firavia said:so you are saying that that F1 will affect f2 and f2 will affect f1 in reverse porcess so we would have equilibriumed torques and sum of torques will be equal to zero ?
The force on one disk creates torsion in the rod that transmits a force to the other disk. Example: Hold a fork by the handle and give it a twist. How come the end of the fork turns when you only touched the handle? Same idea. Another example: Poke something with a stick. Clearly the force of your hand on one end of the stick is transmitted to the object you are poking.firavia said:my second question is :
how does the rod perform a second force or an another way an inverse torque on diske 2 ?
is it due to the transmission of F1 to disk2 number 2 ?
Looking at the system as a whole, I'd say that it makes more sense to say that the resistive torque acts on disk 2. (If I understand your problem correctly. But I'm no mechanical engineer.) But since they are connected, a resistive force on one disk affects the entire system.secondly : the resistive torque is does it exist on both disks or only on disk 2
if it exist on both disks does that mean that the resistive torque on disk 1 is caused by disk2 and the rotation of disk2 is a responisbility of F1 ?
I suspect that they want you to calculate the power you have to apply to overcome the resistive force. F1 is the applied force; F2 is the resistive force (the "load") that you must overcome to make the system rotate. Since the net torque is zero, the applied power just equals the "reverse" power due to the resistive force.and if we have 2 forceson eachdisks why can we say that F1 = power x velocity , why we chose f1 not the resistive torque on disk1 caused by disk2 is it cause the resistive torque on disk1 cause by F2 is eqaul to power x velocit in the spot of action of this resistive torque ?
For many purposes, you don't have to worry about the details of the torsion created in the rod. But sometimes you do: The engineer who must guarantee that the rod is strong/rigid enough will have to worry about such details. That's a bit more advanced.firavia said:I really thank you for your help u gave me the hint of stop thinking about studying the disks alone cause it would complicate my understanding, though if we go deeper inthis study we would understand how the microscopic reactions occur ...
Welcome to PF, Daniel. You are asking good questions; many do not. Good on you.by the way my real name is daniel and I am a 4th year mechanical engineering , internal combustion engine as a major --- I hope u don't think that I am stupid , I know how solves such problems but i like as well to dive deep inside the problem , though we stopped taking these kinds of probelms now , this problem is at my second year of engineering.
Again I really thanks u , u were very helpfull.
A confusing torque phenomena is a phenomenon in which the torque or rotational force applied to an object is not easily understood or predicted due to various factors such as the shape, material, or external forces acting on the object.
A confusing torque phenomena can occur due to a variety of reasons. It can be caused by the shape of the object, such as its center of mass or distribution of weight. It can also be affected by external forces such as friction, air resistance, or other objects interacting with the object. Additionally, the material properties of the object can also play a role in the occurrence of a confusing torque phenomena.
Examples of a confusing torque phenomena can be seen in various sports, such as baseball or golf, where the shape and weight distribution of the ball can affect its trajectory and spin. It can also be observed in everyday tasks, such as opening a door or using a wrench, where the position and distribution of force can impact the amount of torque applied.
Calculating or predicting a confusing torque phenomena can be complex and may require advanced mathematical equations and models. Factors such as the shape, weight distribution, and external forces acting on the object must be considered. Additionally, experimental testing and data collection may be necessary to accurately predict the torque.
A confusing torque phenomena is relevant to science and engineering as it plays a crucial role in understanding the behavior of rotating objects and designing structures or machines that rely on rotational forces. It is also important in fields such as biomechanics, where an understanding of torque is necessary to study the movement and function of the human body.