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Hej Thanks, But you know its very weird. There is this impedance you writing about that is related to the change of voltage and ampere in a coil. However this change doesn't refer to the fact that the electricity is actually charging the magnet the same way. And it is also related to AC not...

You know I dont believe in this, since the charging time must be related to the velocity of the light the coil length and some pretty complex evaluation that relates to the volume of the iron core.. As the electricity goes in it the field already exit from it and the charge propagates toward the...

Its 51.

Well, its like m shape and it size is like 15cm * 10cm * 15cm. Its charging less than in a 0.001 sec. I don't have better equipment to measure smaller time, so I need the calculus... The winding is on the the middle leg of the iron core.

No I am asking about the time requires to load/charge the electromagnet this means how long doest it take until the electromagnet's field builds up from zero...

Impedance is related to AC its a resistance type that relate to AC. Why would I even think on it? It is a DC electro magnet: R = 10.4 Ohm I = 2.0 A U = 20.8 V By the way I know that is in the microseconds to milliseconds range

see my answer above, a DC electromagnet that has 2 amps some hundred turns and a iron core. How long does it take for the electromagnet to reach the maximum electromagnetic field strength B. Just turn the electricity on and how long does it take to get it up and running.

I meant when the electromagnet reaches the designed load. Lets say it was designed to have 2 ams and 50 volts. How long does it take to reach the operating magnetic field strength?

Hej Guys, Did anyone see anywhere an equation to this? If nothing else then a loading time formula for solenoid would do. Thank you!
10. ### I Caculate the reaction force of a radially moving object

Hej it doesnt matter what force is driving that mass outwards. CF or other doesn't matter! In this case the velocity that moves the object out is constant! Anyways I found it out that in my example the results were close enough initially and later I found it out that with bigger systems it is...
11. ### I Caculate the reaction force of a radially moving object

I found that out that this is actually incorrect. Just imagine a large radius disc where the two radial distance is same (on the radius) the first pair is close to the center, the second is further. The circum velocity of the pairs have different ratios. There the force that will accel the...
12. ### I Caculate the reaction force of a radially moving object

It doesnt matter that is an other example and its ok, the point is that by cross calculation you cant get it right in terms of direction but only values. Its really getting annoying and stupid that every second thing have wrong units then we say it doesn't have units or direction that it is not...
13. ### I Caculate the reaction force of a radially moving object

angular velocity is not perpendicular to the rotation it is the rotation itself. https://www.symbolab.com/solver/vector-cross-product-calculator/%5Cbegin%7Bpmatrix%7D0%261%260%5Cend%7Bpmatrix%7D%5Ctimes%5Cbegin%7Bpmatrix%7D-5%260%260%5Cend%7Bpmatrix%7D x/y plane the velocity and the angular...
14. ### I Caculate the reaction force of a radially moving object

Okay, so vector force = [0,1,0] vector angvel = [-50,0,0] In math. cross [0,1,0] [-50,0,0] = [0,0,50] that is out of the plane. Fc = [0,v,0] × [angvel,0,0] * 2.0 * m (min or plus depends on rot dir okay so how is it for you that it is in plane? So this is an official calculus Freactionforce...
15. ### I Caculate the reaction force of a radially moving object

maybe you misunderstood. Velocity dir = centrifugal force dir, object moving outward or inwards would cause the system decelerate or accelerate but the rotating frame remains the same... In physics, the Coriolis force is an inertial force[1] that acts on objects that are in motion relative to a...
16. ### I Caculate the reaction force of a radially moving object

Hello, An object moves outward in shaft radially due to centrifugal force. lest say it weights 1kg . in a timestep=0.0001 it travels 0.0017 meters this is actually the difference of two radius, let say first radius r1 = 0.25 meters second r2 = 0.25 + 0.0017 meters rpm of the rotating system...
17. ### Mechanical question -- Mechanical arm with special constraints

Obviously I thought about the problem I put up. Dont make problem out of it, sorry.
18. ### Mechanical question -- Mechanical arm with special constraints

you figured right, there is no otherwise it would be a perpetual machine LOL! :D
19. ### Mechanical question -- Mechanical arm with special constraints

Its this simple. LOL. Because the p1-p2 work like an arm it would try to lift the pc to perpendicular direction. Obviously the distances are telling that it will be double force there. On the top the single stays. So the self torque would be 500*0.1= 50Nm and the torque from the center it would...
20. ### Mechanical question -- Mechanical arm with special constraints

Please, is this because of summer? Read the post line by line. See how he mixes up elements please. this is why I said off the subject. But BTW I found a solution to this using this vector approach which is fine for this linear forces.. Interestingly the main torque is zero at this angle, but...
21. ### Mechanical question -- Mechanical arm with special constraints

Hej thanks for the answer but please no... You seems to be off the subject, thanks again anyways. Somebody else please?
22. ### Mechanical question -- Mechanical arm with special constraints

What you mean its irrelevant? I have found one law, that if the system have torque then it would be stoppable by an opposing torque only. This somewhat means the same as you said that it doesn't matter. However if the constraint is not stationary then the whole system would move together and...
23. ### Mechanical question -- Mechanical arm with special constraints

Here in this case an arm in special constrain. The arm is capable to rotate around the main center if force is applied to the center. The torque practically generated by the force that is pushing Tarm. Tamr rotates and pulls with more or less the same force at the top that horizontal force then...
24. ### Electromagnet pull force calculation:

I think something is wrong with it. If this would be true you could lift very big weight with few kilowatts and then you could make an impossible machine outputting megawatts. You could pull a piece of metal with great force would result very high torque and if your velocity is high enough you...
25. ### Problem with wheels and arms

please can you be more specific? I mean please only answer if you know the answer. This system must be able to solve by ratios and sin angles. Thanks anyways! [[Moderator's note: Per this request, the level of the thread has been changed from "A" to "B", and several off-topic posts discussing...
26. ### Problem with wheels and arms

Hej, that might be that the system accels, but I belive that it is possible to zero it out, maybe by putting more wheels. Actually on the end If I make sure the calculus is right I will try to convert it to a system that it will generate zeroed systems. If I have only one arm thats easy I...
27. ### Problem with wheels and arms

Dear Physics lover friends, I am in the middle of something and I would like to ask a question on how to solve this branch wheeled problem. The yellow lines are the branches, they have one wheels on them and the wheels are on a circular path. I would like to know how much the normal force A...
28. ### Velocity of the pressure change

Hej guys, Do you know how to calculate the pressure re balancing time in an underwater container where the liquid were de -pressured by taking very small amount of liquid away (just to have the normal enclosed liquid's gravitational pressure there, without the external water column's...
29. ### Magnetic field behind superconductors

Hej Guys, Is there a way to calculate the magnetic field behind a superconductor? I mean the model is like some simple block magnet and a bigger superconductor plate to try to shield the magnetic field. How strong the magnetic field would be above(behind) the SC? B, H is given. Also is the...
30. ### Calculate power required to operate superconducting magnet

thx I look into it.