A solenoid (, from the Greek σωληνοειδής sōlēnoeidḗs, "pipe-shaped") is a type of electromagnet, the purpose of which is to generate a controlled magnetic field through a coil wound into a tightly packed helix. The coil can be arranged to produce a uniform magnetic field in a volume of space when an electric current is passed through it. The term solenoid was coined in 1823 by André-Marie Ampère to designate a helical coil.In the study of electromagnetism, a solenoid is a coil whose length is substantially greater than its diameter. The helical coil of a solenoid does not necessarily need to revolve around a straight-line axis; for example, William Sturgeon's electromagnet of 1824 consisted of a solenoid bent into a horseshoe shape.
In engineering, the term may also refer to a variety of transducer devices that convert energy into linear motion. In simple terms, a solenoid converts electrical energy into mechanical work. The term is also often used to refer to a solenoid valve, an integrated device containing an electromechanical solenoid which actuates either a pneumatic or hydraulic valve, or a solenoid switch, which is a specific type of relay that internally uses an electromechanical solenoid to operate an electrical switch; for example, an automobile starter solenoid or linear solenoid. Solenoid bolts, a type of electromechanical locking mechanism, also exist. In electromagnetic technology, a solenoid is an actuator assembly with a sliding ferromagnetic plunger inside the coil. Without power, the plunger extends for part of its length outside the coil; applying power pulls the plunger into the coil. Electromagnets with fixed cores are not considered solenoids.
The term solenoid also refers to any device that converts electrical energy to mechanical energy using a solenoid. The device creates a magnetic field from electric current, and uses the magnetic field to create linear motion.
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...
Homework Statement
Ok, I need help, but it is for a project my son is working on. I am homeschooling him (13) and he is entered in a local science fair. He has designed an air core solenoid shock absorber for a bike. It more or less works, and we are working our way through the forces...
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...
A solenoid, of sufficient length to consider external flux to be zero, passes through a uniform magnetic field with significant length on both ends extending beyond the field.
Will a torque be exerted upon the solenoid ? Or do the windings effectively mask the internal solenoid field from the...
Hi all.
I am going to build an industrial quality knife-tool to cut cardboard, and I would like to ask you all for any advice, experience and warnings you might have. I'm in the need of a motor to oscillate a knife at a frequency of 200-300 Hz, with a stroke of 1.2mm +/- 0.6mm. The knife it...
Homework Statement
A student makes an electromagnet by winding 320 turns of wire around a wooden cylinder of diameter 4,80 cm. The coil is connected to a battery producing a current of 4.20 A in the wire. At what axial distance z>>d will the magnetic field of this dipole be 5.0 μT?
Homework...
I'm fairly confident I can express the strength of a magnetic field along the axis of a current carrying loop at some distance x away using the Biot-Savart Law. I'm just trying to extend this idea for a solenoid with N turns. I'm assuming that the current would become NI in this case?
Regards
Dan
Homework Statement
Consider a large solenoid aligned with the z-axis with a uniform magnetic field inside given by Bo = Boz[hat]. Contained WITHIN the solenoid is a very large parallel plate capacitor and the plates (one at the x=0 plane and the other at the x = d plane) have surface charge...
Sorry to bring this up again but is there any way of telling how much energy a solenoid will use for a lateral solenoid for a given length and diameter. Is there an online calculator?
I'm interested to know how much energy is lost in the form of resistance/heat as my understanding of how they...
A bar magnet with uniform magnetization is inserted half way into a solenoid, and I am wondering what the force is on the magnet?
The magnet's magnetization is pointing up, which means it has bound surface current circling counterclockwise, and a magnetic field pointing up.
The solenoid...
Homework Statement
A 2cm diameter cylindrical solenoid of 10 loops and 20cm long is in a perpendicular magnetic field of 0.7Tesla directed away from you. The field increases to 2.7Tesla in 100ms. The loop has 8Ω.
What is the EMF?
What is the current?
What is the magnetic field of the...
Homework Statement
We have a solenoid and power supply and a plunger with a mass,
Determine y(t) when v(t)=U(t) (i.e the movement of the plunger when the input voltage is the unit step) use laplace transformes for the current i(s) and for the movement of the mass for a given force.
Probel...
A solenoid of length 45 cm has 340 turns of radius 2.2 cm. A tightly wound coil with 16 turns of radius 4.4 cm is at the center of the solenoid. The axes of the coil and solenoid coincide. Find the emf induced in the coil if the current in the solenoid varies according to I=4.6sin(50∏t)A...
Homework Statement
The point p is located at (3,1,2). An infinitely long straight wire passes through the points (0,0,0)
and (0;1;0) and carries a current of a A in the positive y direction. A finite length of wire carries
a current of b A from (2,0,0) to (2,0,0). An semi-infinite solenoid...
*This isn't a problem so much as needing to fill in the gaps from a lecture where I was taking notes on painkillers due to surgery. The problem statement is my best guess as to what exactly was said by the instructor.
Homework Statement
"Find the mutual inductance (M) of a square-bore...
Homework Statement
See figure attached.
The author claims the field outside this infinitely long solenoid with N' turns and a current i(t) flowing through it is 0, but he doesn't explain why.
Why is it 0? Is there an intuitive reasoning behind it?
Homework Equations
N/A
The...
can someone help with this calculation
two semicircle magnets N-S of strength 'B' encircle a solenoid of length 'L' and move with a constant velocity 'V'. what will be the current 'I' that is induced in solenoid. also, what force will the magnet experience because of this current (Lenz's law)
I am doing A2 Level Product Design (as well as Physics obviously ) and I am making a workstand for a bicycle. It involves a ratchet and pawl mechanism which will be locked out by a solenoid acting on the pawl.
The bike weighs roughly 12.1kg and the ratchet wheel from nylon. The pawl is...
I am doing A2 Level Product Design (as well as Physics obviously :-p) and I am making a workstand for a bicycle. It involves a ratchet and pawl mechanism which will be locked out by a solenoid acting on the pawl.
The bike weighs roughly 12.1kg and the ratchet wheel from nylon. The pawl is...
Hello Forum,
How many turns do we need to make a good solenoid? 50, 40 ,1000?
I know the more turns, the larger N, the better. But what is the minimum number of turns to create a homogeneous B field inside the coil and an almost zero B field outside?
Does the cross-sectional area of the...
Homework Statement
In my physics lab, we were asked to connect an unpowered solenoid to an oscilloscope and then move a magnet through the solenoid and observe the changes in voltage on the oscilloscope. First we were asked to move the north pole of the magnet into the solenoid and then the...
I'm intending on creating a solenoid that will project a bb for a class project. I'm using a flash capacitor from a disposable camera as my current source. Here is my question...what is the best "setup" for the solenoid to increase the magnetic force on the bb without increasing its current...
Homework Statement
We want to construct a solenoid with a resistance of 4.30 Ω and generate a magnetic field of
3.70 × 10−2 T
at its center when applying 4.60 A of electrical current. We want to use copper wire with a diameter of 0.500 mm. If we need the solenoid's radius to be 1.00 cm...
Homework Statement
A single-turn circular loop of radius R = 0.235 m is coaxial with a long 1780 turn solenoid of radius 0.0435 m and length 0.850 m, as seen in the figure below. The variable resistor is changed so that the solenoid current decreases linearly from 6.12 A to 1.46 A in 0.230...
Homework Statement
A single-turn circular loop of radius R = 0.235 m is coaxial with a long 1780 turn solenoid of radius 0.0435 m and length 0.850 m, as seen in the figure below. The variable resistor is changed so that the solenoid current decreases linearly from 6.12 A to 1.46 A in 0.230...
Is it possible to use a solenoid as a shock absorber?
i.e run current through the solenoid, producing a magnetic field opposing a separate magnet attached to whatever it is receiving the shock impulse, thus dampening the effect according to the amount of current input.
I'm looking at redesigning a hydraulic solenoid valve with the aim of reducing the package size. The solenoid coil is by far the largest component of the device, with about 4000 coils arrayed in about 90 layers stacked on top of each other. I'm wondering if I can reduce the size by removing some...
I'm having a bit of confusion applying the left hand rule to find the direction of electron flow in a coil. I'm given the following pictures.
1.)
To use the left hand rule here, I would wrap my hand around the object with my thumb pointing towards the north pole, so my fingers would...
How would the magnetic field of a solenoid change if it used AC current instead of DC current? How would this affect the motion of a charged particle moving from the center to the side of the solenoid?
This isn't a homework problem, just something I'm curious about. Hence, there is no "right"...
Homework Statement
Your physics lab demonstrator hands you a spool of copper wire and a battery (voltage V) and asks you to wind the wire around a hollow, cylindrical, cardboard tube (radius a) to make a solenoid of length 2L.
a) What is the amplitude of the magnetic field at the centre...
Homework Statement
A short-circuited solenoid of radius b with n turns rotates at an angular velocity
about the diameter of one of the turns in a uniform magnetic field B. The axis of rotation is perpendicular to the magnetic field direction. The resistance and the inductance of the...
Homework Statement
http://i27.lulzimg.com/ac8f155fa0.jpg
[PLAIN][PLAIN]http://i27.lulzimg.com/b5f4ac2fce.jpg
Homework Equations
1. B = ((mu(0) * N * I )) / L ,, 2. (mu(0) / 4pi)*((I*(delta(S) cross r(direction)))/r^2)
The Attempt at a Solution
im not really sure which...
Hi, I'm new to the forums, and I'm studying to be an aerospace engineer. I'm still in the start of my program, and I'm not in school till next semester, so this isn't for school.
My question is, what's the effect of interlocking coils that are slightly offset carrying a current in the same...
Homework Statement
A 2000 turn solenoid of length 1.50 m and diameter 5.00 cm has a dc resistance of 3.0. It is
connected to a 50 Hz, 40.0 Volt (rms) ac supply. Find the rms current in the solenoidHomework Equations
Vind = L di/dt
Vind = Induced EMF
Ohm's Law
V-Vind = IR
L = (4pi x 10^-7)n^2 Al...
I'm doing a lab write-up for physics 2. The experiment is about the title, a bar magnet being dropped through a solenoid.
I have to explain four graphs that plot the change in emf (y axis) vs. time (x) axis. There are incoming and outgoing peaks on these graphs. I have to tie these results...
I am attempting to build a device that pulls against a spring at variable tensions, based on how much electricity is passed to it.
I have read that solenoids don't "like" being charged for long without going to a closed position. That they burn out. The specific problem is that the spring...
Homework Statement
A 10 cm long solenoid with 241 turns and radius R = 3.00 cm has a current flowing through it of Io = 200 mA. What is the magnetic field strength inside the solenoid (in T)? The Attempt at a Solution
So i know i have to use the formula B = (uo)(n)(Io)
uo = a constant 1.257 x...
Okay I have a really odd question that might be difficult to answer. I have searched for an answer in several physics books and websites and don't think I have come across a specific answer for this question.
Suppose I were to send a negative electromagnetic charge through a solenoid and want...
Along the center of a very long solenoid tube the field strength is constant. At the ends of the tube, however, the field decays and drops off.
Is there a simple way (mathematical solution or simple trick) to make the field perfectly constant (or to a fraction of a percent tolerance)...
I haven't seen any discussion or any mention what so ever of this before so excuse me if it's that's because it's a crazy idea.
What would be the pros and cons of using solenoids as the rails and projectile of a railgun?
Would the stronger magnetic field of the solenoids allow a stronger force...
Hi Everyone,
I have made a solenoid of 100 turns. When i bring a small permanent magnet near the solenoid, it attracts the North pole of permanent magnet while it should attract the South pole according to right hand thumb rule... now i got confused. Kindly help me.
Regards,
hsn
Homework Statement
A ball ( 2.7 g ) is launched at a 45 degree angle with a solenoid input of 50V. What is the initial speed of the ball?
Homework Equations
KE = 0.5mv^2
PE = mgh
dy = vy(0)t + 0.5at^2
dx = vx(0)t
The Attempt at a Solution
Voltage is potential energy and I...
I have just learned electromagnetic induction and it states that if you move a magnet through a solenoid, you would get an induced current.
Say, if you have a copper solenoid, and if you want to move a magnet through it, there will be something (maybe, a force) that would prevent the magnet...