Solenoid Definition and 705 Threads

A solenoid of length 0.4 m and diameter 0.6 m consists of a single layer of 1000 turns of fine wire carrying a current of 5 x 10-3 A. Calculate the magnetic field strength on the axis at the middle and at the ends of the solenoid. I know the field inside a long solenoid, B = μNI, which is...

I am having some trouble understanding why and how the emf changes when a bar magnet is dropped into a solenoid. As the magnet moves down (have not entered the solenoid yet) it experences an increase in magnetic field. As it enters the magnet it experiences an increase in magnetic still until...

Homework Statement A 27.0-cm long solenoid 1.25 cm in diameter is to produce a field of 0.215 T at its center. How much current should the solenoid carry if it has 900 turns of the wire? Homework Equations B = μIN / l The Attempt at a Solution Why am I given the diameter plus the...

I need a review of solenoid equations, such as equations for bar solenoids, toroidal solenoids, and toroidal solenoids with an air gap within them. I think that somewhere along the line I may have learned something incorrect, so I would like to kill any douts that I have by ascertaining myself...

Some Background I am working on a soccer robotics project called RoboCup (perhaps people here have heard of it), which revolves around building a fleet of autonomous soccer robots that play against each other (league website - http://small-size.informatik.uni-bremen.de/ ). The kicking...

Homework Statement A 10 cm long, 1 cm diameter solenoid contains 500 turns of wire. A current that varies as I = 5Sin(100πt) Amps flows through the solenoid wire. Calculate the magnitude of the magnetic flux at the centre of the solenoid as a function of time using equation (1). Compare this...

I'm looking at this picture from part of an explanation of the torque on a coil of current arranged as a solenoid: http://www.physics.sjsu.edu/becker/physics51/images/28_30_Torgue_on_solenoid.jpg Now, they claim that the torque is directed into the page, but I can't understand why. I agree...

Hi my name is Juan Motta and i´m new in this forum, I`m a total begginer in physics. I´m planning to build a solenoid (air coil or iron coil, i don´t know) with different form, like this: http://www.divshare.com/img/thumb/19310413-b22.jpg And i have some cuestions about, because i...

Homework Statement A solenoid has a radius of 2mm and a length of 1.2cm. If the # of turns per unit length is 200 and the current is 12A, calculate the magnetic flux density at a) the center and b) the ends of the solenoid Homework Equations The biot-savart law: \vec{B} = \frac{\mu_0}{4...

I have heard that when a magnet is moving completely inside a solenoid, there will be no induced emf. Is that true ? Personally, I think even the magnet is moving inside a solenoid with speed v, there will still be induced emf. Assume a magnet is moving inside a solenoid from left to right...

Homework Statement A solenoid of length 20.0 cm is made of 5000 circular coils. It carries a steady current of 10.0 A. Near its center is places a very flat and small coil with a resistance of 2.50 Ω made of 100 circular loops, each with a radius of 3.00 mm. This small coil is oriented so that...

Homework Statement A square loop with side-length a is positioned at the centre of a long thin solenoid, which has radius r (with r>a), length l and N turns. The plane of the loop is perpendicular to the axis of the solenoid, find V_{emf} induced in the solenoid Homework Equations...

Hi all. I would like to do a finite element simulation of a coil in a time-varying magnetic field, to see how much current is induced in the coil, and also to see how the coil itself affects its surroundings. Now my question is, how do I model a coil with several thousand turns in a practical...

Homework Statement First, I will describe the solenoid referenced, as it is from another problem. The solenoid is made by winding a single layer of No. 14 copper wire on a cylindrical form 6cm in diameter. There are 5 turns per centimeter and the length of the solenoid is 30cm. Consulting...

When a magnet is pushed into a solenoid, the solenoid will have an induced emf and hence induced current since it is a closed circuit. But when the magnet is outside does, how does the magnetic field of the solenoid look like? I mean is it combined with the magnet's magnetic field or does it...

Homework Statement Attached file shows the problem statement. The Attempt at a Solution I can do this problem easily. Problem is that there's just one step in my book's derivation that I don't understand. It sets ρ equal to the hypotenuse in the triangle and then says that: dl = ρ/sinθ...

Hello everyone, I'm doing research on solenoid design for satellite magnetic torquers. I've come across a couple of papers that mention "Loney's Solenoid". Does anyone know who Loney is/was and where I can find the details on "Loney's Solenoid"? Thanks. This is my first post. Sorry in...

In Fig. 28.8, a view of the solenoid, showing the clockwise sense of the current in the windings, is given. An electron is in circular motion near the center of the solenoid, with an orbital diameter of 3.0 cm. The speed of the electron and the sense of the orbital motion are closest to The...

Hey, I'm wondering if a short solenoid (50mm) would be able to pull a 300mm core through it if it was open at both ends? Or would the soleniod stop acting once the core had come to the far side? I've attached a pic of what I'm trying to do (forgive the paint drawring). I'm basically trying...

Hey guys! New guy here so bear with me on my first post:) I'm trying to calculate the B field in the center of a finite solenoid for different outer radius sizes. I was able to find a formula online that gave the B field in the center of a solenoid given its length, inner radius, outer...

Hello I want to calculate field of the Solenoid Coil with AC current. For a DC current field is calculated easily from the BiotSavart. What is the process for AC current? Get the L value with RLCMeter in operating frequency? Is there an equation to get the field with...

Homework Statement The mathematical formula that connects the magnetic field in a solenoid with the current is given by B=((μ0 x n)/(2πr)) i where μ0 = 4∏ x 10^-7 NA^-2 is the 'magnetic constant', n is the number of turns or loops of wire (unknown), r is the radius of the solenoid (0.023m)...

I have a solenoid with 180 turns, which is 10 cm long. It has a half core of magnets (which could be constituted as part iron core). The magnetic field strength was measured to be 0.004982 T inside the solenoid around the middle when 12v was run through it and 0.004512 without power running...

Homework Statement I've been given a solenoid and I have N/l = 100 turns/meter, dI/dt = 0.05A/s and a radius of 0.005m. I am only concerned with the dI/dt. Homework Equations B = μ*N/l*I \Phi = \int\int B\bulletn dl \epsilon = d\Phi/dt The Attempt at a Solution For B I get the...

Homework Statement A simple loop of 5 cm radius encompasses the middle turns of a long coil. The coil has 2500-turns, is of length 1 m and radius 1 cm, and carries a current of 10 Amps. What is the magnetic flux through the single loop? Homework Equations B=μIN/L with L=1: B=μIN...

Hey guys, for my engineering course, we are build an autonomous watercraft with a self expanding debris recovery system. My job is the debris recovery system, and part of this system basically using a solenoid to expand the system. The idea is that a frame made of PVC piping, which will...

Homework Statement A solenoid is 0.16 m long and consists of 130 turns of wire. At its center, the solenoid produces a magnetic field with a strength of 2.0 mT. Find the current in the coil. Homework Equations B=μNI/L B=strengh of magnet N=number of loops I= current and L=lengh μ is...

1. A current balance is constructed to measure the force between a solenoid with n=10000turns per length and a straight wire segment of length l=0.05m inside the solenoid and perpendicular to the field. The current through both the solenoid and wire segment is I=14A. What is the B field inside...

Homework Statement polarity of a horseshoe shaped solenoid given symbol for power source large line small line. Current flows through the right end of the horsehoe and out of the left end. The wire is wrapped in a CW direction if looking at the left end of the magnet. The wire is...

Homework Statement There are two coaxial solenoids, each 30cm long. One is inside the other. Each carry a current of 3A, but in opposite directions. Inner solenoid has a radius of 3cm and the outer has a radius of 6cm. Inner has 15 turns/cm and the outer has 30 turns/cm. Find the...

I was reading through an example question calculating the electric field in a solenoid and it made an assumption that the radial electric field must be equal to zero because there is no excess charge in the system. I don't understand when this is true or even why it is true, any suggestions...

A 30mH solenoid inductor is wound on a form 0.4 m in length and 0.1 m in diameter. A coil is tightly wound around the solenoid at its center. the coil resistance is 5.0 ohms. The mutual inductance of the coil and solenoid is 60μH. At a given instant, the current in the solenoid is 0.3A and is...

Homework Statement Connect a battery to a solenoid A cylindrical solenoid 40 cm long with a radius of 8 mm has 250 tightly-wound turns of wire uniformly distributed along its length (see the figure). Around the middle of the solenoid is a two-turn rectangular loop 3 cm by 2 cm made of...

Homework Statement A particular ideal solenoid has 1200 turns/m, a radius of 10 cm, and a current of 4.0 A. An electron is fired from the axis of the solenoid in a direction perpendicular to the axis. What is the maximum speed the electron can have if it is not run into the side of the...

Homework Statement A wire circle of radius 0.050 m is embedded in a solenoid of length 0.20 m with 1000 turns that carries a current of 0.50 A. If a vector that is normal to the plane of the circle makes a 40° angle with the axis of the solenoid, what is the magnetic flux through the loop...

I know an electromagnet can be created by wrapping a wire around a metal tube and putting some current across the wire. This creates a magnetic field. my question is why does the magnetic field decrease when the metal tube is removed leaving just the wire?

Homework Statement A very long solenoid of circular cross section with radius a= 4.80 cm has n= 77.0 turns/cm of wire. An electron is sitting outside the solenoid, at a distance r= 5.30 cm from the solenoid axis. What is the magnitude of the force on the electron while the current in the...

I am trying to make a .4 Tesla AC (50Hz) magnetic coil. Originally I used ID-38MM, OD-155MM & Length of Solenoid 50MM. Using 3.5MM X 1.5MM wire 380 Turns. I get 0.27 Tesla at 75Amp. but the wire allows me to work only for around 5 Min with Forced air cooling. I do not know the relationship how...

Homework Statement "A solenoid is wound with 400 turns on a form 4cm in diameter and 50 cm long. The windings carry a current that produces a magnetic field, of magnitude 1.5mT, at the center of the solenoid. The magnetic flux through the solenoid is closest to? Homework Equations...

Say I have a solenoid that has a magnetic field Bo Sin(ωt) passing through its axis. What will be the EMF induced in the solenoid as a result ? I know it'll be a function of Cos (ωt) but I am more interested in how my choice of the solenoid will affect the EMF that I'll ultimately measure...

I decided to make a couple solenoids. Not too many loops on them though as I need higher gauge wire. After getting that I put one in the other and in that a core of metal that had some iron in it. I tried inducing a bit of current in the outer winding by driving DC current through the inner coil...

Homework Statement A long solenoid has 100 turns/cm and carries a current i. An electron moves within the solenoid in a circle of radius 0.022 cm perpendicular to the axis of the solenoid. The speed of the electron is 0.048c (c is the speed of light). Homework Equations f = m*v^2/r =...

Problem: Calculating the eddy current distribution inside an infinitely long cylindrical conductor inside a straight and infinitely long solenoid energized by an alternating sinusoidal current. The problem has a perfect summery and we know that magnetic field and the eddy current depend on...

Homework Statement long solenoid of n turns per unit length is wound upon a cylindrical core of radius a and relative permeability. The current I through the solenoid is increasing with time t at a constant rate. Obtain expression for the rate of increase of stored energy per unit length...

Homework Statement A certain solenoid(50cm long with 2000 loops) carries a current of 0.70A and is in vacuum. An electron is shot at an angle of 10deg to the solenoid axis from a point on the axis. Find the speed of the electron if it is just to miss hitting the inside of the 1.6cm diameter...

Homework Statement A 200-turn solenoid is 20.0 cm long and carries a current of 3.25 A. Find the magnetic field. Find the force exerted on a 15.0 µC charged particle moving at 1050 m/s through the interior of the solenoid, at an angle of 11.5° relative to the solenoid’s axis. Homework...

Hey everyone, I'm looking for some references on solenoid design - core materials, geometry, etc etc etc. Can anyone suggest me some canonical references that I should check out? All the books I've found are from the 60s or so. Thanks!

Homework Statement A solenoid is wound with a single layer of insulated copper wire of diameter 2.100 mm and has a diameter of 3.000 cm and is 1.900 m long. Assume that adjacent wires touch and that insulation thickness is negligible. a) How many turns are on the solenoid? Solved...

when you place a magnet into a solenoid with a ac current it will get demagnetised. So does this mean that the magnetic field will go into the magnet in the opposite direction of the magnet's own magnetic field? and disalign it. meaning will the magnetic field enter the magnet as though it is...

Hi I know that for a short solenoid (L<R) the magnetic field at the axis is (standard EM) B(z) = \frac{1}{2}\mu_0 \frac{N}{L}I(\frac{z+\frac{L}{2}}{\sqrt{(z+L/2)^2+R^2}} - \frac{z-\frac{L}{2}}{\sqrt{(z-L/2)^2+R^2}}) where R is the radius of the solenoid, N the number of turns along the axis...