Magnetism Definition and 952 Threads

There are two hemispheric magnets, both of them have S on the outer surface and N on the inner surface. If I put them together to form a hollow ball, assuming they are so close that no empty space in the interface, what happens to the magnetic field (inside and outside)? Since magnetic field...

My book says that there is not net magnetic force between two non-magnetic materials. Shouldn't there be a little magnetic force rather than 'no net force' between two non-magnetic substances. Aren't they successful to influence the atomic currents of other to a considerable degree? How is...

Hi, I have two questions that come from a unique example of magnetism. Here is the scenario: a thin and long piece of iron is placed in between a magnet and the north pole faces the outing sheet and some iron tacks. The iron tack do not get attracted to the iron even though a south pole is...

Was wondering how Jupiter's hydrogen liquid core converts the energy to create a magnetic field? and How exactly do these properties behave? I understand that my phrasing of the Question might be odd and may be wrong but i was just wondering how it worked

Hi, I need a little help trying to determine the possibility of magnetizing and demagnetizing an object. My question is as follows: Is it possible to line two different slabs of thick glass with magnetic strips that can be magnetized to one another for the purpose of holding them together...

* Dozens of animal species, from ants to whales, have well-documented abilities to detect the geomagnetic field and use it for orientation and navigation. * After some false starts, researchers may have now located the organs for this magnetic sense, and they are finally understanding the...

Homework Statement A stationary loop of wire is placed in a magnetic field directed into the page as shown below. (the image shows a magnetic field like this and a circle in the middle to represent the loop) X X X X X X X X X X X X X X...

Homework Statement A charged oil drop is allowed to fall through the electric field created by the plates as shown: + - l l l l l l In order to give the oil drop a straight trajectory, a magnetic field should be established with...

What is the cause for diamagnetism and other types of magnetism? Is it related to Farady's law or quantum mechanical properties of matter?

So suppose we have two objects, both with positive charge Q Coulombs and X meters apart. And now suppose Object 1 has a mass of m1 and Object 2 has a mass of m2. In other words, the charges are identical, but masses are not. So each of these will have an Electric Potential Energy of -QEΔX...

I have just created a short animated video explaining all the concepts of electromagnetism. It is at: http://youtu.be/XiHVe8U5PhU I put a lot of of time and effort into making the animations, so please take a look at this, and please pass it along to anyone who you think might be...

My question is how do I find the voltage across a capacitor? I have an RLC circuit with a switch and battery. It only gives me the values for the battery, L, C, and R. My main question is, is there an equation or something to find the voltage across a capacitor?

I was watching some FX yesterday and Robert Downey's best, IronMan was on. I got to thinking, if possible, how does his little energy producing circle actually works. The idea is this: Picture a circle lined with magnets all facing negatively inward. In the center is a blade with parallel...

Homework Statement A magnet is hung by a string and then placed near a wire as shown. When the switch is closed, the magnet rotates such that the ends of the magnet move as indicated by the arrows. At the instant the switch is closed determine: a) the direction of the current through the...

Ok they say a magnetic force can never do work on an object.ok but can anyone explain this to me? a particle is set in a velocity in the x direction, magnetic field in the y direction so dat the resultant magnetic force be in the z direction at this instant. Hence the particle moves in a circle...

I am a biochemistry major and I need to take the first two introductory physics courses as a prerequisite to physical chemistry. I can take regular pchem, which requires calculus based physics or pchem for biochemists, which only requires the algebra based physics. With the way my university...

This isn't really a homework problem or a problem that I can just figure out. I'm wondering why the letter B represents the magnetic field. Also, what does H represent? (For example, F represents the "force" field, E represents the "electric" field, V represents the scalar voltage. I'm actually...

Would there be any difference of resistive magnetism created in a Syncronous Motor used for a generator as opposed to other types of motors? Reason being is that I'm doing some research on generators for my own personal advancement and was wondering if there was a way and proceeding...

If it were true that non-inertial motion, such as spin, is required for magnetism to exist, then one could say that a lack of non-inertial motion implies lack of magnetism. However, whether a separate body is traveling inertially or non-inertially in relation to spacetime is not something...

hi,guys do you know when the coin will fall from a magnet and when would it stay on it?

Urgent Help Needed on Saturation, Coercivity and Energy Stored in a magnetic field! Hi guys, I'm applying to university to study Natural Science and the deadline to apply is Friday. In my application it's crucial I demonstrate extra ability and I thought of using a recent idea I had when...

What is origin of magnetism in dielectric crystals?

Hi all. I am a student taking A levels, I was hoping the forumites here could help me answer some doubts that I have regarding the concepts above. 1) Waves It was mentioned that the distances between resonances are half a wavelength. For example, in a water tube with a sound source...

In order for magnetism to be present doesn't electricity have to be present? A electron moves from a negative charge to positive charge and magnetism is the motion of electric charge, resulting in attractive and repulsive forces between objects. It seems to me that if a negative and positve...

I read in Stephen Herman's Electrical Studies for Trades: 4th Edition that 'internal gravity' causes electrons to spin on their axes, resulting in magnetism. How do electrons' spins result in flux?

What are the causes of magnetism?

What exactly is magnetism on a particle level? I'm currently doing physics at school and we are doing a unit on electricity and magnetism. I can ACCEPT that a magnet has two poles and like poles repel and unlike poles attract. I can ACCEPT that a wire carrying current produces a magnetic field...

They say it is impossible to know whether you're moving at constant velocity or at rest unless you look outside. How about this:(no gravity please) I take two known charges and hold them at a distance one above the other. They repel.That is l I know. Someone else outside says,that the...

Homework Statement Dear Members, Diamagnetic substances acquire magnetism due to orbital motion of electrons paramagnetic substances acquire magnetism due to interaction between magnetic dipoles Ferromagnetic substances acquire magnetism due to domain structure. This is what my...

Fig.35 shows a light and flexible conducting loop X freely hung on a smooth horizontal rail. A bar magnet PQ approaches the loop from the right. Which one of the following descriptions about this process is correct? A If P is a N-pole, the loop will be repelled to the left and its area...

I was working with Maxwell's equations recently when I remembered Gauss' Law for gravity. I couldn't help but wonder if there was some sort of parallel between gravity and electricity, in the sense that one might be able to construct "Maxwell's Equations" (obviously they wouldn't really be his)...

Hello, I am nearing the end of my first year. I will have 1-2 months of vacation. I am really interested in getting grasp at least a little around magnetic phenomena. If somebody could recommend me a book where this issue is addressed hard. Where magnetism is explained, but not on the...

Magnetism is said to arise due to relativity. When an extended charged object move, length contraction occurs which increases the objects charge density thus increasing electric field which is then perceived to be caused by magnetism (if we do not account for relativity). Thus, magnetism is a...

Hi, I had a question in my exam at my college that I did not quite know how to answer. Why is the study of magnetism more important than of electricity in technology ? (I can't remember exactly the question)

My classmates had an argument. There are 2 trolleys; one of them (A) is attached to a solenoid wrapped around a soft-iron core, which is connected to a d.c. circuit. There's another trolley (B) which is attached to a solenoid wrapped around a soft-iron core but it is connected to a load...

Homework Statement Four point charges have equal magnitudes. three are positive and one is negative, as the diagram shows. they are fixed in place on the same straight line, and adjacent charges are equally separated by a distance d. consider the net electrostatic force acting on each...

Homework Statement Hey guys, I have an incredibly broad question, just revising the topic of Magnetism, On the topic of reluctance, As I have learned so far, Magnetic Circuits and electric circuits have similar properties. When the core is a "series" network, you add Reluctance together...

If an irregular shape such as a tetrahedron is magnetised, where will the poles be?

I'm currently in an electricity and magnetism physics course and we're using the 8th edition of Serway. I'm looking for a review type book that focuses on problem solving with examples and explanations rather than theory. Here are the topics we are covering throughout the course: 23...

Homework Statement Hi guys. I'm stuck at a question that has to do with magnetism and I would really appreciate some help! The question is: "An electron and an alpha particle are in a magnetic field and moves in circles with the same tangential speed. Calculate the ratio between the number...

Can magnetism exist independently of current or charge? I'm just curious because the intertwining relationship between E&M.

Magnetic fields are present in space. Doesn’t Ampere-Maxwell law state this is a consequence of currents or changing e-fields? Why in astrophysics is the emphasis on magnetic fields and no emphasis on currents and changing e-fields that cause these magnetic fields? Does modern astrophysics...

Hello: Many many years ago I walked away from community college with an associates degree in physics, and despite my fondness for the subject, I had to put it aside for other things. I recently happened upon something that lead me to realize how much I had forgotten, and so I've decided to...

Homework Statement http://ploader.net/files/795e05b46860aa55fc17ce371c14eb99.PNG The Attempt at a Solution http://ploader.net/files/574a81d69c34f39fd049610251d0f0bd.GIF Ok so I got the first part of the question. The problem that I am having is the direction of the field lines, which...

Yes, yes I know about the template, but these questions are so basic that I don't really know what I can show as work... Sometimes all I need for help is the relevant equation itself -.- So please don't delete or hate. Thanks! 2. http://tinyimage.net/images/50136173150204648365.png The...

Homework Statement A force acts on a rectangular loop of wire, pulling it out of a magnetic field. Calculate the force required to pull the loop to the right at a constant speed of 4.42 m/s. B = 0.44 T l = 0.350 m v = 4.42 m/s R = 0.356 ohms Homework Equations Fmagnetic=I*l*B...

Homework Statement What is the Kinetic Energy of an electron that passes undeviated through perpendicular electric and magnetic fields if E = 4.0 kV/m and B = 8.0 mT? m_{e} = 9.1 \times 10^{-31} \textup{kg} q_{e} = 1.6 \times 10^{-19} \textup{C} Homework Equations I got stuck doing...

Hello everybody Basically as the topic states: How can you calculate "The spatial wavelength of a Halbach array" (symbol lambda)? Context: The reason I ask is that since I've got bored during my easter holidays I decided to try a wee science project and try and make a model of an...

I'm stumped on a problem about Gauss' Law for Magnetism because I don't know what "local form" is. From context, I suspect that local form refers to the expression of an equation with the del operator (i.e. del x E = (charge density/(E0)), but I'm not sure. I've been self-teaching with Tipler...