Wiley Interdisciplinary Reviews (abbreviated WIREs) is a set of peer-reviewed scientific journals that each publish interdisciplinary review articles on high-profile topics. The series was established in 2009 and is published by Wiley-Blackwell. Each journal publishes new review articles every month.
The journal series won the 2009 R.R. Hawkins Award from the Association of American Publishers.
Homework Statement
Shown at right is a cross-sectional view of two long straight wires that are parallel to one another. One wire carries a current out of the page; the other carries an equal current into the page. I don't know how to show the diagrams, but the current into the page is at...
Homework Statement
Wires A and B, having equal lengths of 40.0 m and equal diameters of 2.60 mm, are connected in series. A potential difference of 60.0 V is applied between the ends of the composite wire. The resistances of the wires are 0.127 and 0.729 , respectively.
Determine:
(a)...
Homework Statement
The circuit shown above consists of a single battery, whose emf is 1.4 V, and three wires made of the same material, but having different cross-sectional areas. Each thick wire has cross-sectional area 1.4e-6 m2, and is 21 cm long. The thin wire has cross-sectional area...
Homework Statement
Two infinitely long wires are separated by a distance of d = 1.4 meters. Both have current running in the positive y direction. A charge of q = +2.7 micro-Coulombs is moving in the positive y direction at v = 3.1 E 6 m/s a distance of r = 0.22 meters from the wire on the...
Homework Statement
Two wires have current both running in the positive x direction as shown in the diagram with I1 = 13.9 amps and I2 = 4.5 amps. They are separated by a distance of d = 4.7 meters. A third wire with I3 = 10 amps is placed somewhere between the two wires with current running...
Hey all,
What I'm trying to do is find a way to affix a wire or group of wires to the frame of an FSAE car to keep them out of the way. Last year this was done by either tie-wrapping the wires to the frame (tie wrap around the frame tube & wire) or with electrical tape by the same manner...
Recently in physics I've learned that equipotential surfaces are always conductors in electrostatic equilibrium.. so no moving charges. I'm a little confused, then, of how a wire carrying current is considered an equipotential? If charges are moving how can the potential be constant?
Recently in physics I've learned that equipotential surfaces are always conductors in electrostatic equilibrium.. so no moving charges. I'm a little confused, then, of how a wire carrying current is considered an equipotential? If charges are moving how can the potential be constant?
Homework Statement
Two current carrying wires cross at right angles (like a + sign).
Wire 1 has current directed horizontally to the left. Wire 2 has current directed vertically up.
If the wires are not restrained, what statement best describes the motion of the wires?
A) Wire 1...
Homework Statement
Two infinitely long parallel straight wires carry currents in the +- z direction as shwn in the figure below. Each wire is located on the x-axis a distance of a from the origin.
a) Determine B as a function of y along the line x=0
b) Sketch a graph of B vs. y along the...
I am lost in the middle of a vast desert in my swim shorts. There is nothing anywhere around me as far as you can see. In front of me is a 12volt battery (say lead acid) with no markings or other indicators of polarity. there are 2 wires long enough to make a connection to the emergency...
Homework Statement
Two parallel loops are parallel, coaxial, and almost in contact, 1.29 mm apart. Each loop is .117 m in radius, the top loop carrying 137 A clockwise, and the bottom look carrying 137 A counter-clockwise. Calculate the force that the bottom loop exerts on the top...
Homework Statement
Consider two parallel conducting wires along the direction of the z axis as shown below. Wire 1 crosses the x-axis at x = -1.10cm and carries a current of 3.50A out of the xy-plane of the page. Wire 2 (right) crosses the x-axis at x = 1.10cm and carries a current of 6.20A...
The diagram (see picture) depicts two long horizontal straight parallel wires that are a distance d=20.36cm apart and each carries a current of 3.25A in the same direction, out of the page. What is the magnitude of the magnetic field at a point that is a perpendicular distance r=30.82cm from...
A long wire carrying a 5.0A current perpendicular to the xy-plane intersects the x-axis at x=-2.0 cm. A second, parallel wire carrying a 3.0A current intersects the x-axis at x=2.0 cm. At what point or points on the x-axis is the magnetic field zero, (a) if the currents are in the same direction...
Homework Statement
Two wires are tied to the 200 g sphere shown in figure. The sphere revolves in a horiIzontal circle at a constant speed of 6.80 m/s.
http://img684.imageshack.us/img684/6537/knightfigure0761.jpg
Homework Equations
Ca=m*v^2/r
f=ma
The Attempt at a Solution
I...
Homework Statement
The four wires that lie at the corners of a square of side a=5.10cm are carrying equal currents i=2.40Amps into (+) or out of (-) the page, as shown in the picture.
Calculate the y component of the magnetic field at the center of the square.
Homework Equations
B...
1. Homework Statement
Two straight wires, each with a resistance of 0.170 ohm and a length of 3.90m, are lying parallel to each other on a smooth horizontal table. Their ends are connected by identical, non-conducting, light springs, each spring having an unstretched length of 1.08 cm. A wire...
NOTE: This is NOT a homework question. I was reading a physics textbook for fun (doesn't everyone nowadays?) and could barely got through the first couple of page the chapter on electric currents because this question was not addressed in the book.
Question 1) If you connect the negative and...
wire 1 has a current of 1A directed into the page, wire 2 is 20 cm to the right of wire 1 with a current of 1A, what direction does this current have to flow in order for the magnetic field strength at the mid point between them to be non zero ?
from the right hand rule the mag field from...
Homework Statement
An underground telephone cable, consisting of a pair of wires, has suffered a short somewhere along its length (at point P in the Figure). The telephone cable is 6.00 km long, and in order to determine where the short is, a techician first measures the resistance between...
Homework Statement
A long pair of wires conducts 20.2 (amps) od dc current to, and from, an instrument. The wires are 23mm apart, what is the magnetic field 9.7cm from their midpoint in their plane?
Homework Equations
B=(µo/2pi)*(I/d)
The Attempt at a Solution
µo = 4pix10^-7...
Hey guys i have no idea how i would accomplish this, I am pretty sure i would made to make some sort of circuit but what i need it to be able to change where 4 wires go from a momentary switch like these.
an example would be to change which usb port a usb cable is connected to by the push of...
Homework Statement
Two very long thin wires carrying equal and opposite currents of 103 A are placed parallel to the x-axis at y=0 and z=+-0.5. Calculte the magnetic field B in the x-y plane and determine it's maximum gradient.Homework Equations
I'm having serious trouble understanding the...
Current in "ideal" wires. - circuits
I am trying to get a "complete" picture of what happens in circuits. I know how to solve typical physics circuit problems using kirchhoffs laws and what not, but I am trying to get a "picture" of what is happening inside of the circuit itself in terms of...
http://img192.imageshack.us/img192/9421/31387291.png
I know that the magnetic field coming off the wire will be directed in a circle counterclockwise around the wire. So, from what I understand, it would work something like this:
http://img709.imageshack.us/img709/1880/70281684.png...
Homework Statement
Electricity from the power plant with a power P = 100MW is transmitted by V= 220kV line. At what distance from the wire is the density of the magnetic field equal to the density of the Earth's magnetic field B(earth) = 4 × 10^-5 T? What is the force on the L= 200 m long...
Hi All,
As I understand it, a voltage impressed across a wire produces an electric field within the wire and in the direction of the wire which causes the movement of electrons.
If two parallel wires carry a direct current, this field exists in both wires.
Now when we talk about...
Homework Statement
Two parralel wires are 8 cm apart. The magnetic field halfway between them is 300 uT. What equal currents must be in the wires? Consider parralel and antiparralel currents
Homework Equations
I use Ia=Ib
B = (u*i) / (2*Pi*distance) where distance = 0.04 m (0.08m...
Homework Statement
The wires on a violin have a cross section of 5.1*10^-7m^2. The wires are put under tension by turning the wooden pegs. The Young Modulus of Steel is 2.0*10^11 Pa.
Calculate the tension required to produce an extension of 4*10^-4m.
Homework Equations
Thats where...
1. Two Identical wires denoted A & B are part of an electric circuit and therefore carry some currents. The wires are characterized by resistance per unit length,r, and both have length, L, each are spaced by a distance, a. What is the magnitude, F, of the force the wires exert on each other? Is...
1. Two Identical wires denoted A & B are part of an electric circuit and therefore carry some currents. The wires are characterized by resistance per unit length,r, and both have length, L, each are spaced by a distance, a. What is the magnitude, F, of the force the wires exert on each other...
Homework Statement
Homework Equations
B = \frac{\mu_o i}{2\pi d}
The Attempt at a Solution
To do this, you'd find the magnetic field magnitude due to the left wire, and add it to the magnetic field due to the right wire. Correct?
If so:
Wire 1:
B = \frac{1.26x10^-6...
Homework Statement
A bag of cement of weight 350 N hangs from three wires as suggested in the figure below. Two of the wires make angles θ1 = 50.0° and θ2 = 27.0° with the horizontal. Assuming the system is in equilibrium, find the tensions in the wires.
Homework Equations
Newton's...
Homework Statement
In the picture below, the two wires carry current i1 and i2, respectively, with positive current to the right. The charge q is positive and has velocity v to the right.
If i2 = 0 and i1 is greater than zero, then the force on q points into the page.
If i1 = 0 and i2...
Tensions in Wires :)
Homework Statement
A 10.0-kg picture is held in place by two wires, one hanging at 50.0o to the left of the vertical and the other at 45.0o to the right of the vertical. What is the tension in the first wire? What is the tension in the second wire?
Homework Equations...
Problem:
Suppose wire A and wire B are made of different metals, and are subjected to the same electric field in two different circuits. Wire B has 5 times the cross-sectional area, 1.1 times as many mobile electrons per cubic centimeter, and 2 times the mobility of wire A. In the steady state...
I have four parallel wires carrying equal currents of 2 amps arranged in a square (see picture attachment for clarification) The figure is an end-view of the wires and each side of the square has an equal length of 0.1m. The direction of current is -Z for A, B, and C; and the direction of...
I've tried to find this repeatedly in my textbook, but my teacher told us to ignore the book and then didn't do a great job explaining it, but here goes...
A conventional current is flowing into the page (-Z direction) along a straight wire placed at the origin O perpendicular to the page...
Homework Statement
Two long cylindrical conductors (wires) of radii a1 and a2 respectively are separated by a distance d >> a1, a2. Find the capacitance per unit length for the system. If d=0.5cm and a1=a2=a, what must be the diameter of the wires to give a capacitance per unit length of...
Hi Guys,
For my design project, I am dealing with a horn antenna that has coaxial wire for the input and output. The problem is, I need to take the signal recived from the antenna by the coaxil and feed it to another circuit, since I need to us a circuit to down convert the freqeuncy or...
Hi, if I have 3 naded wires copper, Tin and Lead wrapped into one cable and I run 12v through it how do I work out the amount of resistance I get and the total voltage at the other end?
Homework Statement
dB = 12mm (0.012m), dC = 20mm (0.02m),
E = 140GPa and the coefficient of thermal expansion, α = 12e-6/°C.
Homework Equations
δ = (R*L)/(E*A)
The Attempt at a Solution
Please see picture for my attempt.
I don't know how the thermal expansion, which...
Homework Statement
http://img33.imageshack.us/img33/4547/walker4ech22pr054.jpg
Two long, straight wires are oriented perpendicular to the page, as shown in the figure . The current in one wire is I-1 = 3.0 A, pointing into the page, and the current in the other wire is I-2 = 4.0 A, pointing...
Why do they always get so tangled when they're in my pocket? I can put them in there completely untangled, then when I pull them out a couple minutes later, they're tangled up badly.
Hello there PF. I'm currently attempting to repair an old headset of mine that had the cord broken. The only thing is that I can't get the wires to make a connection. I know that wires such as these have a special coating on them that prevents shorts when they're bundled inside insulation bare...
Homework Statement
Each current depicted below by an “x” flows into the screen. At which of the following points (A, B, C, or D) is the magnetic force on a charge the largest?
A_______B_x___C__D_x______
------------1---------2
Note that C is equidistant from both wires...
Homework Statement
Let two long parallel wires, a distance d apart, carry equal currents I in the same direction. One wire is a x=0 and the other is a x=d. Determine B along the x-axis between the wires as a function of X.
Repeat problem if wire at x=0 is 2I and in the opposed direction...