Electricity Definition and 999 Threads

Homework Statement A wire is moved with constant velocity such that the motion is perpendicular to the length of the wire in a region containing magnetic field perpendicular to the plane of motion. The wire has a resistance R. Will thermel energy be generated in the wire? Homework Equations...

My professor says resistance depends on, R\quad =\quad \frac { \rho L }{ A } And is defined as, R\quad =\quad \frac { V }{ I } What does she mean? What is the difference? A definition is denoted by \equiv, what is the difference between that and an ordinary equal sign?

Homework Statement A circular rod has a radius of curvature R = 8.11 cm, and a uniformly distributed positive charge Q = 6.25 pC and subtends an angle theta = 2.40 rad. What is the magnitude of the electric field that Q produces at the center of curvature? Homework Equations E = kQ/r^2 6.25 pC...

Homework Statement A charged particle (either an electron or a proton) is moving rightward between two parallel charged plates separated by distance d=2.87mm. The plate potentials are V1=-75.8V and V2=-49V. The particle is slowing from an initial speed of 90.0 km/s at the left plate. What is...

I Have a Dumb Question. If Electricity Supplied from Substation to Feeder to Transformer and Under Transformer If There Are Many Consumers. Assuming That many Consumers Went on for a Holiday, Does Utility Still Pay for the Electricity to the Generation company for the Electricity they Supplied...

Homework Statement A metal sphere of charge +6μC is surrounded by a metal shell of net charge +6μC. Which of the following diagrams represents the electric field lines of the system? Homework EquationsThe Attempt at a Solution The correct answer provided by my teacher is a figure with 12...

OK, so I've gone through probably 90 tutorials on electricity and related topics, and there's a bundle of terms I ran into, used by people ages 12-80 with a dozen different accents and twice as many time zones. (So I'm not sure how many terms are universal and how many are provincial). Live...

Homework Statement Three point charges are located on the positive x-axis of a coordinate system. Charge q1 = 1.0 nC is 2.0 cm from the origin, charge q2 = -3.5 nC is 4.0 cm from the origin and charge q3 = 6.0 nC located at the origin. What is the net force ((a)magnitude and (b) direction) on...

Homework Statement Show how you can make a mathematic formula for maximum power, by using the other formulas. I think, that U is maybe called V in English. Homework Equations U= R*I Up = -ri *I+U0The Attempt at a Solution [/B] P=I·(-ri·I+U0)P= -ri·I2+U0 I

When we looked at some closed surface, we defined the overall electric flux of that surface as the sum of all infinitesimal fluxes of all the infinitesimal surfaces that make the quoted closed surface. Does that change if we do not have a closed surface, but a rigid body such as, let's say, a...

Homework Statement A square wire loop 12.0 cm on each side carries a clockwise current of 15.0 A Find the magnitude of the magnetic field at its center due to the four 1.30 −mm wire segments at the midpoint of each side. Homework Equations B = (μ0*I)/(4π)*(2a)/(x√(x^2+a^2)) The Attempt at a...

Homework Statement A square wire loop 12.0 cm on each side carries a clockwise current of 15.0 A Find the magnitude of the magnetic field at its center due to the four 1.30 −mm wire segments at the midpoint of each side. Homework Equations B = (μ0*I)/(4π)*(2a)/(x√(x^2+a^2)) The Attempt at a...

More specifically, how to conduct electricity through water without submerging electrodes into water? I can't think of other way except using high voltage to arc across air into water, but this method only work for high voltage. Any ideas? Thanks

Or even better, generate in 4-Phase, convert to two-phase for transmission. Even number phases cancel out nicely (contrary to popular belief, 3-phase does not actually cancel out). 2-phase might be convertible back to four phase for the purpose of industrial motors. Forgive me for speaking out...

Homework Statement A circular uniform laser beam has a power of P = 3.2 mW and a diameter of d = 8.5 mm. The beam is a form of electromagnetic raditation with both electric and magnetic field components. (a) Calculate the intensity of the beam in units of W/m^2 (b) Calculate the energy (delta...

Homework Statement Suppose the electric field between the plates P and P' in the mass spectrometer in following figure is 1.89×104V/m and the magnetic field in both regions is 0.668 T. If the source contains the three isotopes of krypton, 82Kr,84Kr, and 86Kr, and the ions are singly charged...

Homework Statement Hello everyone, I am new here and have a question regarding method of images in my electricity and magnetism class. I need help to even get the ball rolling. The question is as follows: a) What is the image of a dipole, oriented toward the center of the conducting sphere, if...

it's an old book of science, where can I find all those old science work to study science through its history?

Homework Statement Protons are projected with an initial speed of v0 = 10^5 m/s into a region in which a uniform electric field E = 800N/C [down] is present. The protons are to hit a target that lies a horizontal distance of 10.0 mm from the point at which the protons are launched. a) find the...

Homework Statement [See the figure attached] a) Find the relation between velocity of electron v and current I. b) Because of the magnetic force on the electron they move at the edge of conductor as shown in the figure and create a electrostatic force that oppomagnetostatic force. Find the...

Homework Statement An object with charge q = −4.00×10−9 C is placed in a region of uniform electric field and is released from rest at point A. After the charge has moved to point B, 0.500 m to the right, it has kinetic energy 5.00×10−7 J .What is the magnitude of the electric field? Homework...

i have studied that a conductor is equipotential and charges don't flow through it but how does it flow through a wire?

http://imgur.com/6iPdcyJ http://imgur.com/6iPdcyJ This question may sound stupid, but I'm curious. Can the electric motor generate electricity if you spin the axle rod? Do the positives and negatives gain charges? EDIT: Image may not work, http://imgur.com/6iPdcyJ

Hey guys I'm a sophomore in college currently taking physics 2(intro E&M), Multivariable calculus, and Differential Equations. I was hoping some of you guys could recommend some good books for intro mechanics and E&M. I'm currently using University Physics by Young in my E&M class, and I used...

Okay guys It's no wonder I love electrostatics I keep on getting so many doubts Okay my doubt goes like this Consider 2 charges(q1and q2 having masses m1and m2 (here i am assuming that these two aren't point charges and therefore don't have negligible volume/mass) Okay so i am neglecting the...

Homework Statement In figure 1, take the half-cylinder's radius and length to be 3.4cm and 15cm respectively. If the electric field has magnitude 5.9 kN/C, find the flux through the half-cylinder. Hint: You don't need to do an integral! Why not? Homework EquationsThe Attempt at a Solution I...

For example can an object be very conductive to electricity but be a very poor conductor of heat and vise-versa, or is a good conductor of one always a good conductor of the other and a bad conductor of one always a bad conductor of both? If they are related, then how and why are they connected...

I need to make a time keeping apparatus that doesn't require electricity. It needs to be something I can make at home and can obtain the resources from a local department store(menards or Home Depot etc.). Any suggestions?

Simple level question this: How many kinds of electrons are there? Like if 1 Amp = 6.24 x 10^18 electrons and Watts = Amps x Volts then in our local 240V system the watts = 240. = 0.24 kW. Now if we take that 1 Amp in an American 120Volt system then the Watts = 120W. So the same stream...

Homework Statement A slab of insulating material has thickness 2d and is oriented so that its faces are parallel to the yz-plane and given by the planes x=d and x=−d. The y- and z-dimensions of the slab are very large compared to d and may be treated as essentially infinite. Let the charge...

Homework Statement All bulbs are identical, (no information given on resistance so assuming all the same) All the switches are closed and then S1 is opened, Does bulb 6 get brighter, dimmer or stay the same? Does bulb 4 get brighter, dimmer or stay the same? Explain briefly why. Homework...

i know that all conductors are equipotential,then how are charges flowing in a conductor?and at times in we say that charges won't flow since two points are equipotential(like in wheat stone bridge we say that charge won't flow across the capacitor/resistor since the ends of the 5th...

Homework Statement A charge (q) is placed in-between two other equal charges named Q. Q-----q-----Q a) If both Q's are positive, is charge q in equilibrium? If yes, is it a stable or unstable equilibrium? b) What about if one Q is negative while the other is...

Can someone please explain to me why, a changing magnetic field can produce an electric field and a changing electrical field can produce a magnetic field. Also how do magnetic fields originate, what causes them?

Homework Statement A capacitor 1 of 3nF is charged with 3 volts. When it is completely charged, we connect it to an uncharged capacitor 2 of 7 nF. Calculate the charge on each capacitor after they reach electric equillibrium. Homework Equations Q=CV The Attempt at a Solution my confusion is...

So I was thinking, if the body has its own electrical currents... especially in the brain, then the brain must have an electrical field that extends infinitely. If that is the case can the brains electrical field interact with the real world and influence it. So for example if the field was...

Hello everyone and happy new year! I would like to ask why it takes so long to create nuclear fusion power plants. The world's first nuclear fission power plant to generate electricity was started in 1954, some nine years after the nuclear fission bomb was detonated. Now we are more than 50...

So the frequency in the power grid is 50 - 60 Hz depending on country's electrical standard. If I have a ~2000 watt heater that runs on 220 volts ~ 9 amps at 50 Hz, would increasing or decreasing the frequency effect the power output of the device. For example if I make the device run at 75 Hz...

How does KIP: Fundamentals of Electricity and Magnetism compare against Purcell? Are they at the same level? Or would focusing on Purcell be a better option? I took an honors EM class and are assigned text was Purcell. It was the first time our school used Purcell for an honors sequence...

Hi, I've been working on a problem for some time now and I can't figure out why exactly this happens, and I've been looking for some insight. The phenomenon can be seen in this video. We can see that the oil rearranges itself due to a high-voltage electric field. Thinking about this, my...

Hi Everyone, I'm currently developing a waste heat recovery device as a side project. The system I've created uses a solution of acetone and water. One step in the process involves vaporizing acetone from the water at a low grade heat temperature (note: acetone does not form an azeotrope with...

Hello everyone, I am currently working on a project to design a more efficient method of electricity production in the nuclear industry. I haven't been able to find anything online (and chemistry isn't exactly my strong suit most of the time), but I wanted to know if anyone knows of a liquid or...

Homework Statement Book says "Substances with a simple molecular structure do not conduct electricity. This is because they do not have any free electrons or an overall electric charge". Homework EquationsThe Attempt at a Solution I think the statement is a generalization because water is a...

Two pith balls, each with a mass of 5.00g, are attached to non-conducting threads and suspended from the same point on the ceiling. Each thread has a length of 1.00m. The balls are then given an identical charge, which causes them to separate. At the point that the electrical and gravitational...

In chapter 5 of Purcell's Electricity and Magnetism, he shows using principles of special relatives that the magnetic force of a current carrying wire on a moving charge is equivalent to the charge experiencing an electric force in its own frame of reference. His argument is that when the...

Hey guys :) new here, Just a simple question to get started. looks like a great forum :D Is the following statement correct or incorrect? If I hold a normal magnet with north and south poles, and I move my hand in one direction parallel to copper wiring, will it generate...

Hi, I've been doing reading on Halbach Arrays moving over surfaces and generating repulsive forces. From my understanding, the moving magnet induces a circular electric current in the metal track, which gives rise to a magnetic field. However, I'm having trouble understanding why this field...

What gives it this property?

Hi, [FONT=PT Sans] I'm trying to figure which is more fuel efficient, turbine vs stroke generators. This honda stroke engine generator does 1000w for 3.8 hrs with 0.6 gallons of fuel or 2.3 liters, so the power per liter of fuel is 1,300 kW...

The 4 questions have been uploaded as 2 jpeg files. I need step by step proper solutions as a pdf or word file if possible. Please help. Send the solutions to my email id : pyplx7x@gmail.com