Magnetic fields Definition and 644 Threads

Hey all smartie-pants! So this is the problem I have a tough time with: The magnetic field perpendicular to a single 13.2-cm-diameter circular loop of copper wire decreases uniformly from 0.750T to zero. If the wire is 2.25mm in diameter, how much charge moves past a point in the coil...

A 3.4g bullet moves with a speed of 160 m/s perpendicular to the Earth's magnetic field of 5x10^-5T. If the bullet possesses a net charge of 13.5 x 10^-9 C, by what distance will it be deflected from its path due to the Earth's magnetic field after it has traveled 1 km? I am confused. Do I...

I have tried everything to solve this problem, and I just cannot come to a conclusion. If anyone finds it comes easy to them, help will be greatly appreciated. :) Here goes: A straight stream of protons passes a given point in space at a rate of 1.5x10^9 protons/s. What magnetic field do...

A cyclotron designed to accelerate protons has an outer radius of 0.477 m. The protons are emitted nearly at rest from a source at the center and are accelerated through 610 V each time they cross the gap between the dees. The dees are between the poles of an electromagnet where the field is...

Hey, i have this question to solve.. An electron has a velocity of 1.62×104 m/s (in the positive x direction) and an acceleration of 2.25×1012 m/s2 (in the positive z direction) in uniform electric and magnetic fields. If the electric field has a magnitude of 19.1 N/C (in the positive z...

Consider the current loop in the figure below. Figure: http://east.ilrn.com/graphing/bca/user/appletImage?dbid=1450953670 Determine the magnetic field (in terms of a, I and d) at the origin. So I will use mu as the permeability of free space. Since the two vertical wires have opposite...

A very long straight wire carries current I. In the middle of the wire a right-angle bend is made. The bend forms an arc of a circle of radius r as shown in the figure below. Figure: http://east.ilrn.com/graphing/bca/user/appletImage?dbid=1161207397 Lets say the permeability of free space...

A metal rod having a mass per unit length p carries a current I. The rod hangs from two vertical wires in a uniform vertical magnetic field as shown in the figure below. The wires make an angle theta with the vertical when in equilibrium. Determine the magnitude of the magnetic field...

A 0.245-kg metal rod carrying a current of 10.5 A glides on two horizontal rails 0.480 m apart. What vertical magnetic field is required to keep the rod moving at a constant speed if the coefficient of kinetic friction between the rod and rails is 0.100? Again I am supposed to use the...

A conductor suspended by two flexible wires as in the figure below has a mass per unit length of 0.0800 kg/m. What current must exist in the conductor in order for the tension in the supporting wires to be zero when the magnetic field is 2.60 T into the page? Figure...

The rotor in a certain electric motor is a flat rectangular coil with 86 turns of wire and dimensions 2.60 cm by 3.80 cm. The rotor rotates in a uniform magnetic field of 0.950 T. When the plane of the rotor is perpendicular to the direction of the magnetic field, it carries a current of 7.3 mA...

Hello. :rolleyes: Do some materials have a magnetic field when electricity runs through them and they are in the superconductive state? Do they lose energy because of that field? Thank you. Miro

We all know that magnetic fields come from moving charge or electron spin. However if it were possible to have protons as a moving charge in a wire does that cause a B field? At first I thought that it obviously should but then I thought about how accelerating electrons emit EM waves...

Is the beauty and color to the Ring Nebula due to synchrotron radiation of particles (electrons) with higher energy (spin) being blueshifted the closer they are to the white dwarf at the center? If so is it the magnetic field that spins the electrons intensly and the futher away the electrons...

Hi, This is my first post on this forum. My question is How is motion of plasma controlled through magnetic fields since it is electrically neutral. My understanding is that since plasma conducts current, a current is passed through plasma and then a magnetic field is applied which...

[FONT=Comic Sans MS]I need help answering the following question: The energy of an electron in the p-level of an atom is changed in the presence of a magnetic field of magnatude 3.4T. What is the difference between the largest & smallest possible engergies? Thank you!

Magnetic Fields! I have to choose which of these are true false. And they are really confusing me. I know that the equation is F=qvB. However I am not sure what makes the problem different with constant velocity. Any help would be wonderful Consider a charged particle moving with a...

Can anyone help me with this? "A research lab has a magnetic facility, which can produce intense, pulsed magnetic fields. In 1 experiment, a B-field of 40 T is to be produced over a cylindrical volume, 40 cm in length and 20 cm in diameter. The energy required to pulse the magnet is...

I am so glad I found the link to this test, so I can reference questions with figures. let me write the problem first, and provide the link at the end, and in between explain where I was stuck. 87) two small pith balls, each carrying a charge q, are attached to the ends of a light rod of...

PART 1. Magnetic Field of Electron The electron and the proton both have Magnetic Moments. By definition (Penguin Dict. of Physics, 1991) the term Magnetic Moment means: 1. SYMBOL, m,: "A property possessed by a permanent magnet or current-carrying coil, used as a measure of the...

Hi, does anybody know what approach to take with the following problem. An electron is accelerated from rest through a potential difference of 500V, then injected into a uniform magnetic field. Once in the magnetic field, it completes half a revolution in 2 ns. What is the radius of the...

An article by W Tucker and K Tucker at NASA says that neutron stars have magnetic fields. If a magnetic field is created by moving charges, and neutron stars have not net charges to move, how are the fields created?

Is a magnetic field carried by a particle? If two north ends of a magnet are brought together they push apart as if they were two rivers meeting head on and if a north pole and a south pole are brought together it is like two rivers flowing together in the same direction. What are these...

It seems that a great deal of research has and is being conducted with regards to generating magnetic fields of enormous density. What is the aim of this research, or is just "pure" research? In other words, is there any speculation that such fields locally distort space-time or could...

How do I determine how much current a wire can safely handle? I made some electromagnets with some coil and 9 volt batteries, but the wire and the batteries get real hot after a minute, which I assume is not good so i don't keep it connected for long. I want to know how much the wire I am using...

I have a few problems that I'm not sure how to do (not sure what equations to use), can anyone help me? 1) At a certain location, the horizontal component of the Earth's magnetic field is 2.3 x 10^-5 T, due north. A proton moves eastward with just the right speed, so the magnetic force on it...

A 1.59 m long wire weighing 0.0668 N/m is suspended directly above an infinitely straight wire. The top wire carries a current of 32.4 A and the bottom wire carries a current of 24.5 A. Find the distance of separation between the wire so that the top wire will be held in place by the magnetic...

For what reason is a magnetic force vector perpendicular to the magnetic field vector and the velocity vector of a charged particle? I know F=qvBsin and how to compute cross products but why does the force make a particle move in that particular direction? Is relativity involved?

Near the Earth's equator, the Earth's magnetic field is approximately horizontal. What current would have to flow through a long wire with a mass density of 10g/m to keep the wire floating in mid-air? What would be the direction of the wire, and the current in the wire? Well, I know I'd...

Hi, I'm currently doing an research experiment into the behaviour of plasma around magnetic fields. I will be using an arc welding machine for the plasma and an electromagnet. (So I can adjust the field's intensity as an independant variable.) The arc should bend in the presence of a magnetic...

Here's my problem: A particle with charge 4.5E-19 C travels in a circular orbit with radius .465 m due to the force exerted on it by a magnetic field with magnitude 1.7 T and perpendicular to the orbit. a) What is the magnitude of the momentum p of the particle? I used the equation...

Here's my problem: A particle with charge 4.5E-19 C travels in a circular orbit with radius .465 m due to the force exerted on it by a magnetic field with magnitude 1.7 T and perpendicular to the orbit. a) What is the magnitude of the momentum p of the particle? I used the equation...

I have been driving myself crazy trying to figure out this problem, for a while now. I just can't get the right answer. should the number of turns be multiplied or divided by the radius? Please help me out. Two circular coils, concentric and lying in the same plane, produce magnetic...

Howdie all, I'm soo glad I found this forum, people are genuinely working together instead of ignoring their fellow physics brethren =) A pair of square parallel conducting plates, having sides of length .05 meter, are .01 meter apart and are connected to a 200 volt power supply. An electron...

Does the following equation mean that electric field E and magnetic field B are always perpendicular?? the equation is: Curl E = - (partial derivative of B with respect to t) where E is time dependent too.

I've read in my textbook in the elecromagnetism chapter, when a particle is negative and goes through the magnetic field the velocity is opposite to the current...I don't really understand this, can someone please explain this?

Are fields like magnetic fields made of particles/waves that travel from the source outwards? For example, if you put an obstacle(that would not let photons pass) between the source and a charged object, would the charge be affected? Or do fields interact with objects independantly from what's...

I have simple question here that I've been wondering about for sometime now, and here it is. In classical physics when an charge is accelerated it creates an oscillating electric field which creates an oscillating magnetic field, a electromagnetic wave, and each field carries energy with it. So...

[SOLVED] Magnetic fields qustions I don't understand the correlation between the two following source of magnetic fields: 1- Electric Dipole 2- Moving Electron I can't build a concept that allows me to explain them both! Are they both caused by moving electrons? #2 is by definitions...

Didnt think that this should go in the theoretical physics section, but if it should feel free to move it. We all know that a large gravitational field can bend light, but my question is would it be possible for a large enough magnetic field to bend light? I know that this doesn't happen...

Hiya ppls! I have some questions about magnetic fields and current flows in general. Lets say in these eg., A vertical wire carries a current straight up in a region where the magnetic field vector points due NORTH. What direction of the resulting force on this current? EX1) No using...

My physics teacher gave the class a brief explanation of a permanent magnet. If I understood him correctly he basically said the special condition with a permanent magnet is that all the electrons are circling uniformly (in same direction). The poles of the magnet are based on the direction the...

I've recently heard someone discussing the effects of pulsed magnetic fields on aluminum. Thats really something I hadn't thought about, but would a pulsed magnetic field on the order of 1 Tesla cause a reaction in Aluminum? How about Stainless Steel? I know these materials usually show no...

It is a known fact that neutron stars and pulsars, remnants of super nova explosions, have very strong magnetic fields. It is said that the collapse of the core amplifies the magnetic field of the progenitor. This is due to the fact that the magnetic fields lines are drawn closer together during...