Magnet Definition and 912 Threads

I found this equation as a solution to the original problem of a point-like ball rolling without friction in a parabolic cavity from Lagrangian mechanics: Is it possible to add an extra force to this equation? I want to add a "magnet" at a certain position that will affect the ball. The...

What would happen if we tried forcing a bar magnet into a magnetic field created by a solenoid (look at the picture)? Assume that both the bar magnet and the solenoid are isolated form any other source of a magnetic field. What I am thinking: First of all, if we tried forcing the north side in...

I am using an exremely stong magnet to deflect a diamagnetic substance( in this case water) Is the magnet being deflected against the dianagnetic Or is the defection only present in the diamagnetic substance?

Hi, there! I am studying magnetism right now and I can’t understand how does a magnet work. I read that the magnet has a magnet field, which influences only charged particles with velocity. But then how does magnet attracts metal objects, e.g iron nail? I read that in metals there are free...

should I be expecting a higher amplitude at resonance for a mass that's heavier to an extent form another where each is attached to a spring vertically , I assumed that's true since the heavier mass will stretch the spring more meaning when moving like a sin or cos wave the amplitude...

I'm doing some modeling of a bending magnet in FEMM, to use as a magnetic spectrometer, and came across the following equation: with the setup of the magnetic spectrometer similar to the following figure: At first I modeled a hard edge scenario in a 2D cross section, where no fringe fields had...

$$\mu = 4\pi \times 10^{-7}$$ $$n = \frac{180}{0.135} = 1333.33$$ $$I = 1.85$$ $$L = 22.619$$ $$r = 0.014$$ $$F= \frac{\mu \times 1333.33 \times 1.85^{2} \times 22.619}{2 \pi \times 0.014}$$

Sorry, I guess I should have remembered all of this from my school days, but right now I have forgotten so much that I need some help. I am developing some simple experiments for school children (age ca. 12). This one involving magnets. I am not asking for detailed calculations, that is way...

The Biot-Savart law gives us the magnetic field created by an electric current. We can calculate the force exerted on a moving charge by this magnetic field using Lorentz's force formula. But my textbook doesn't address the repulsive or attractive force between like or unlike poles...

https://biomedscis.com/fulltext/the-effects-of-solar-activity-and-geomagnetic-disturbance-on-human-health.ID.000203.php ''m) Solar activity may contribute to the development of and be a trigger of the exacerbation of nervous and mental disorders, such schizophrenia, Alzheimer's disease, and...

Hi, electromagnetism is definitely not my area of expertise. However, I sometimes get to deal a bit with simulations of electromagnetic problems. One thing that bothers me now and I can't find the answer to it is whether magnetization ##M## is different for north and south pole of a magnet...

Other than the most simple school stuff of attraction, repulsion and "lines of force", I've never studied magnets. Hence this question. On the left we have a disc magnet diameter D attracted to a much larger lump of steel with force F (when there is no gap between)...

Hi, very trivial question, sorry, but I did not find the answer on the net. I have a robotic vacuum cleaner, https://i02.appmifile.com/248_operator_sg/07/03/2023/b083a6129f828ac367c4600b0a78b85b.jpg?f=webp and it's constantly bumping into and trying to climb on the massive iron one-pilar foot...

I have few cylindrical neodymium magnets of same diameter and different heights and different magnetic inductions in the geometric center of the magnetic pole surface. Knowing those values of magnetic induction, how can I measure what the induction is at a certain distance from that center? For...

Electrons have a magnetic dipole moment. If a permanent magnet was held against one end of a copper rod, the delocalised electrons close to the magnet would be attracted and concentrate around the magnetic pole. This should result in the creation of a weak electret because of the uneven...

Magnetic field lines are loops, so at the surface of a magnet (axially magnetized) cylinder) pole they look like this? there is a dead zone at the center where there is no lines/magnetic field present? or perhaps they look more like this? lines converge in the middle to a single line or point...

Howdy. My kids and I like to experiment with things, we're looking to play around with some permanent magnet experiments and when I googled a question it brought me here, so I figured, heck, might be able to get my questions answered as well :)

I stumbled upon this video on YouTube: Here is a screenshot with some colored lines added of the part that generated a few questions in my head that I hope some of you smart folk can answer for me. In the video, the spherical magnet (at the end near the two big magnets) appears to increase...

Following the Picture below, If I Conduct current through Permanent magnet Bar and hold the battery still. Will the magnet move in any direction ? Thank you.

This happened a long time ago, and I haven't found the answer. I posted a post on the Internet, and no one gave an explanation, so I really hope to find the answer. A magnet, no matter which pole is facing up, will rotate counterclockwise, as shown in the figure below. The magnet will not spin...

I cannot explain that if I divide a magnet with a north and a south pole into 2 parts, the force in it rearranges itself into 2 poles. Where is the center of power? How can I explain the principle of magnetic force if I don't take it as a matter of fact.

For the problem attached, Why is the magnetic Flux not zero through the loop? Many thanks!

Hi ... I have answered this question and I think that F/mg equals 3. But I've asked it from someone and he told me that F/mg is 4. Can someone help me find out which one is correct ??? My answer :

I am working with HS students on measuring Current Gradients in Copper for their science project " Current Gradients in the human body during surgical cauterization". Next year I was thing of putting a thin sheet of Copper over strong magnets and using the Voltage gradient to draw the Current...

Hello all! I have a earring project with magnets involved but no magnet expert involved :( Here are a few stupid questions I hope someone can help us with! BACKGROUND: We are designing magnetic earrings. The earrings are meant to clamp the ear with 3 different levels of pressure. The magnetic...

I know I should use a limit $$B=\lim_{r\to l}{\frac{\mu}{4\pi}\cdot \frac{4rml}{{\left({r}^2-l^2\right)}^2}},$$,but in Wolfram I get a weird solution. https://www.wolframalpha.com/input?i2d=true&i=Limit[Divide[4rl,Power[\(40)Power[r,2]-Power[l,2]\(41),2]],r->l] What is the solution? It...

How are the poles of a tapered magnet distributed? Is there any way to calculate its magnetic force?

Is any physical explanation of this effect?

As can be seen below we have 3 ring magnets. The middel one floats in between the other two. We want to know how to calculate the air friction of the middle ring magnet if this rotates.

Dear readers, I have a question regarding permanent magnets and the force they generate on particles, which is far from my comfort zone. I have the option on using two types of permanent magnets and with two different setups. Imagine that we want to attract small particles using the magnets...

I understand the iron fillings become little magnets all pointing in the same north south direction similar to the spin aligned electrons in the permanent magnet. Similarly, a compass near a wire traces out the magnetic field lines ie North/South. My question is how do I reconcile the fact that...

Hi I'm doing my extended essay (like a research paper) for the IB and I'm having a bit of trouble with my setup and data process. The plan for my experiment goes something like this: I have a magnet wrapped in wire strapped to a battery and a superconductor in liquid nitrogen. After levitating...

I know that for a single cylindrical neodymium magnet, the formula $$ \displaystyle{\displaylines{B(z)=\frac{μ_0M}{2}(\frac{z}{\sqrt{z^{2}+R^{2}}}-\frac{z-L}{\sqrt{(z-L)^{2}-R^{2}}})}} $$ shows the relationship between the magnetic field strength and the distance between the magnet. I was...

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Curious to know if possible to create an electromagnetic field around a skyscraper if you run sufficient current through the structural members (ie interconnected column and beam network). Thanks in advance to any takers...

I am currently working on an experiment that involves dropping a magnet from varying heights and measuring how the induced emf of a solenoid changes as a result. I am currently somewhat struggling with a derivation for a relationship between the two variables, however, this is what I have been...

So I'm looking for some advice on a problem that I am trying to solve for a project. I'm an engineer but my background in vector mathematics is very minimal so I'm looking for some assistance. Lets assume we have a permanent magnet. We know the characteristics of this magnet, such as it's...

The changing magnetic field of a falling magnet induces currents in the pipe that slows it's fall through the pipe. Question: If the induced currents are decreasing the magnets descent then they must themselves have momentum. How is it dissipated once the magnet has passed through the end of...

So I'm familiar with the magnet falling through a copper tube demonstration that shows the induced magnetic fields slowing the magnet down. I know that this experiment is also possible with a conducting coil as long as the coil forms a closed circuit. I'm trying to find a way to calculate the...

Hello All : Good day : i found a small magnet and it reacted strangely with my body , the magnet is 5 mm in diameter , and less than 4 mm thickness , i rob it few times on my left hand vain it stuck , which i do not understand why ! i checked on other people about 3 one of them had the same...

If a electrically charged mass travels thru a magnetic(m) field, it will accelerate at right angles to its velocity and the m-field. Under some conditions like this the charged mass will travel in a circular loop due to this magnetic force acceleration. This info is all over the internet. e.g...

[Mentor Note -- Two similar thread starts merged into one] Hey all, I have been working on this project for a while now, which features suspending an object midair through the use of magnetic levitation principles. Cool right? And so I have been researching and trying, even finding ground...

Hi Dear, I have a single-component (Z-Axis) magnetometer with 60nT resolution. I want to calculate the maximum distance that this magnetometer can detect an N52 magnet with a volume of 1 cm³. So I used the following formula and inserted the values, and finally calculated the Z...

I do not fully understand why a falling neodymium magnet is decelerated in a vertical copper pipe. It is usually explained by Lenz's law, two induced currents generate an upward force that counteracts the force of gravity. (link) However, I assume this upward force has to be generated by the...

I’d like to build a high speed generator using a diametrically opposed magnet. I’m asking if when using a diametrically opposed magnet rotating on a shaft if the generator coils can simply be a continuous wound loop around the magnet like a electro magnet is wound therefore only requiring one...

I have a magnet that will lift only 1 lb of steel with an electric lift. If I discharge a big capacitor into a 1000 turn coil with the magnet in the center of the coil it super charges the magnet it will lift 200 lbs for about 4 seconds. The magnet has a half life of about 4 second for about...

is it possible to create a remote that can control the force acting on a magnet? for example is, to stop one magnet from attracting or repulsing other metals. or making a magnet adjust the force it apply to other object.

I'm trying to simulate a Magnetostatic problem. In my model there are two coils and a reciprocating permanent magnet. I defined a parameter, Xpm (movement of permanent magnet) in x direction to imply the reciprocating movement of permanent magnet like a piston. Xpm = f(t). I defined "t" as sweep...

Hi. My question is described in the summary. I'm seeking some advice. The Reissner-Nordstrom solution for charged spherical bodies seems to indicate that electrostatic fields will be a source of gravitation. I've not seen anything similar for magnetic fields but I can't imagine how it could be...