Current Definition and 1000 Threads

Homework Statement Homework Equations The Attempt at a Solution [/B] My question: in order to find the answer for part d, I have the L, the B, and the mass. However, the F equations have I, which I do not have. Would I have to solve for I in order to find F? If so, I would like some...

Homework Statement Calculate the time-dependent magnetic field intensity B(t) at an axial distance r from a long, thin straight copper wire that carries a sinusoidal current with an alternating frequency of 50 Hz and a maximum amplitude of 0.5 A. Homework Equations I = Asin(\omega t) B =...

Homework Statement (Is the image read-able now? ) The fig 1 shows the relationship between voltage and current when voltage is applied to a certain light bulb. Next, in fig 2, the bulb is connected in series with a 12-V battery and a 5 ohm resistor. Question : what is the amount of power...

The Feynman LECTURES ON PHYSICS (NEW MILLENNIUM EDITION) by FEYNMAN•LEIGHTON•SANDS VOLUME II discusses radiation from an infinite sheet of switched-on constant current in section "18-4 A traveling field" on page 18-15. The solution shows a constant E field and constant B field at a given point...

Homework Statement Find the current Ig[/B] Homework Equations [/B] V1 = R1/(R1 + R2) * Vs 1/Rtotal = 1/R1 + 1/R2 + 1/R3...exampleThe Attempt at a Solution I know what I did wrong, but I don't know how to avoid it. Here's what I mean. How do you know which way its suppose to be?

Homework Statement Why is my calculated total resistance of the circuit higher than the resistor used in series and the theoretical total resistance? In a series circuit I used a 100Ω resistor and measured the current at 1.0v intervals from 1.0-5.0v. At 1.0v the current was 8.70mA using a 100Ω...

Homework Statement Two parallel wires have currents that have the same direction, but differing magnitude. The current in wire A is I, and the current in wire B is 2I. Which one of the following statements concerning the situation is true? A) Both wires attract each other with the same force...

Homework Statement Homework EquationsThe Attempt at a Solution When the circuit moves creates magnetic force that moves the some charges in the wire and that is a current. That is what i thought. F = Q.v B sin theta B = ( permeability Of vacuum* I)/(2pi.r) But how to find the I? Thank you...

Does static charge near to a constant current carrying conductor experience force on it? I am asking this question because i have learned that electric field and mangnetic field are same thing but viewing differently with respect to the frame of reference...when a positive test charge moves (...

What are the current values for Friedman's scalar and its first derivative with respect to time? Thanks.

Homework Statement In the picture 20.40, what is the direction of the current induced in the resistor at the instant the switch is closed.[/B]Homework Equations Right hand rules- Point thumb in direction of current and your fingers will curl in direction of magnetic field. Lenz's law. The...

Hello, I'm current studying magnetostatics and I'm struggling to understand the equation for A. Here is the equation from Griffith in the attachment. My confusion is, if the object is a cylinder and the current density is a function of s, J(s), then how would I write r-r'? Thank you!

Homework Statement In the picture at points A and B are two thin parallel wires, where traveling currents are 15 A and 32 A to opposite directions. The distance between wires is 5.3 cm. Point's P distances from A and B are the same. Calculate the magnetic flux density at point P. Homework...

Homework Statement The problem states: Determine the voltage labeled v in the following circuit: https://ibb.co/hz0Q37 The variable is the voltage across the 2 ohm resistor. The ground I chose for this example is located in the center of the circuit. Homework Equations V=IR I guess. The...

Homework Statement Find the current and potential difference through 3Ω resistor. Homework Equations ε - I1 (Ω) - I2 (Ω) ... = 0 The Attempt at a Solution I only got as far as finding the equation: ε - I1 (3Ω) - I2 (16Ω) = 0 (For complete loop around circuit) I know I have to find I1, but I...

I was wondering what would happen if you have a current carrying wire that makes an angle with the magnetic field and how to describe its motion. Prepare yourself for the bad drawing. I will first show how the method I used works for a simpler case where Magnetic field and current are...

Homework Statement A long wire with a current changes direction by 90 degrees. Calculate the magnetic field at the point at a perpendicular distance of S from the wire before it changed direction and a distance of T from the segment of the wire after it changed direction. Homework Equations I...

Since the classical Hall EMF is proportional to current, in an alternating current circuit, the Hall Emf should also follow an alternating pattern. Is it so? Or the Hall Emf doesn't change in a sine wave pattern instead remains more or less same and has a voltage based on the average/rms...

Homework Statement a. What is the net resistance in the circuit? b. What is the current through the 4 Ω resistor? c. What is the voltage drop across the 3 Ω resistor? Homework Equations R12 = R1 +R2 R34 =R3 + R4 1/Rt = 1/R12 + 1/R34 I3=I4 The Attempt at a Solution a) R12 = 2+ 3...

Homework Statement Homework EquationsThe Attempt at a Solution The current will decrease , as a result an EMF will be induced in the cylinder . The EMF induced E = -dΦ/dt I am assuming magnetic field through the cylinder to be same as that at the center of the a current carrying coil...

Ok so I haven't been on here for a while but I can't seem to find an answer to my question anywhere and really need some help! So I not only am an electronics hobbies but I have fun installing car audio systems as well. The problem I am running into is that I would like to run an alt wire...

Why does current produce a static magnetic field, but a static magnetic field doesn't produce current? Specifically, why is one true, but the inverse not true? I can accept that each rule individually is just how the universe works... but it sounds so contradictory when I examine both together...

Hi all, Sorry in advance if my questions are stupid and the answers are obvious. I can see from P=VI why a high power appliance requires more current to function. However looking at ohms law and I=V/R it’s telling me that greater resistance will lead to less current. I've always figured that...

Homework Statement Describe the magnetic field you would observe if two coils were connected with magnetic fields pointing in opposite directions. Homework Equations No equation The Attempt at a Solution If the magnetic field was pointing in opposite directions, would it mean that it would...

Homework Statement Determine the Full Width Half Maximum (FWHM) using the single coil equation and fitting parameters. The FWHM is the measure of how broad (wide) a signal is before it loses half of its intensity. In this case, its a measure of the distance spanned before the magnetic field...

Hello Everyone, I am still trying to get my head around what a current to voltage converter (and vice versa) is. There is a section on my book, in the chapter about op amps, that discusses this topic. Apparently, a current signal is less susceptible to noise than a voltage signal... But what...

Homework Statement A series RLC current having a resistance of 40ohms and inductance of 400mH and a capacitance of 300microfarad is energized from 50Hz, 200V A.C supply. Find i) Resonance Frequency of the circuit ii) Peak current drawn by the circuit at 50Hz iii) Peak current drawn by the...

Homework Statement [/B]Homework Equations I calculated for RMS current. The Attempt at a Solution How to know whether they've asked RMS or Average current? Isn't Output always RMS? Average value is of no use anyways.

Homework Statement Q1: A power plant produces energy at a voltage of Vi = 18667 V. Before being sent along long distance power lines this electricity is sent through a transformer with 143 turns in the primary coil and 8971 turns in the secondary coil. Voltage is calculated to be...

Homework Statement The problem is simple, all I have to do is draw a voltage / time graph. The black ring is a conductor, its inner surface area is 0.01 m^2. The magnetic field points upward, B = 4T. 2. The attempt at a solution I understand what I have to do, but I'm getting the wrong +/-...

Homework Statement Given the known quantities ##R, C, L##, ##k##, and the effective values of the voltages ##E_1=E_2=E_3=E## , ##w = \frac{1}{\sqrt{LC}}## of the direct-symmetrical 3-Phase system find the expressions for the effective values of ##U_{12}##, ##U## and ##I## and calculate the...

Homework Statement Three very long parallel conductors situated in the air make a direct-symmetrical 3-Phase system. The conductors pass through the A B C points of the triangle of side ##a##. The currents in the conductor form a direct-symmetrical 3-Phase system. Effective values of currents...

I read online that insulation rating of the conductor depends on the voltage rating and not on the current. Can some one explain me how current doesn't contribute to insulation rating? Am i missing something? Kindly explain me

Homework Statement Pic A, what's the I2? Pic B, what's the current across a-b ? Homework Equations V = I*R Voltage in series is different, the current is the same Current in parallel is different, the voltage is the same The Attempt at a Solution from Pic A, I found that I1 = 1A, I3 = 1A...

regards my question is how each coulomb of charge can lose (transfer ) energy when going from a to b when electrons are very slow the definition of potential difference: is how much each coulomb of the charge loses (transfer ) energy when going from a to b an example to clarify the question...

Hey all! Today I took my car to the shop for some starter issues. They told me that the starter had been damaged by a battery with a higher CCA rating than was safe for the starter motor and it burned out my motor slowly over time. I feel like they may be BS'ing me, but I'm not sure. I know my...

Homework Statement A current of 1600A exist in a rectangular (0.4 x 16 cm) bus bar. The electrons move at an average velocity of v. If the concentration of electrons is 1029 per cubic meter, and they are uniformly distributed, what is v? Knowns Current (i) = 1600A = 1600 x 1018 aA Charge per...

Homework Statement [/B] Hi I am looking at this action: Under the transformation ## \phi \to \phi e^{i \epsilon} ## Homework Equations [/B] So a conserved current is found by, promoting the parameter describing the transformation- ##\epsilon## say- to depend on ##x## since we know that...

I hoped to use a Keithley 2400 source meter to generate a ~120Hz AC signal by outputting a 2-point sweep from 1A to -1A on an infinite trigger. The waveform image is attached below. The end goal is a resistance measurement for bulk semiconductor materials, we prefer AC measurement to avoid...

How does electrical current have energy? (when electrons move very slowly through circuit)? (mentor note: removed cross link)

I'm interested in what kind of energy has electric current ?. For everything I taught in school should have kinetic energy because electrons are on a certain potential within the electric field when the switch is closed then the electrons move and the electric current is "generated" which then...

I am studying induction motors and i have equation for instantaneous value of current flowing in each phases.(please check to image below).I can see that its it the form Im.cosωt But isn't it supposed to be Im.sinωt ?because that's how we find all instantaneous parameters like voltage and...

i'm trying to research what might be the difference in two electrical scenarios scenario same in both scenarios- we have a 18"tall x 4"deep x 8" wide carbon steel box, this is mounted to a building and electrically bonded to the electrical system throughout the building and most of the rest of...

I am trying to calculate the ripple current in boost converter for ∆i1 and ∆i2 between time intervals between DT and T, and also dependent on the voltage level (Vin or Vin-Vout). To find a formula for ∆i1 and ∆i2, two formulas have to be derived for them. This is done from the equation: I...

Are the electrons of a conductor so loosely bound that just moving a current might give rise to a tiny bit of current owing to electron's inertia??

Homework Statement [/B]Homework Equations For 1st I think answer is B For second I(c) = B I(b) B is beta The Attempt at a Solution For 1st I think it's B But book says answer is D Is book wrong? For second I'm getting: I(c) = 3mA And beta = 200 So I(c) = B I(b) 3mA = 200 I(b) This gives I(b)...

<< Mentor Note -- thread moved from the technical forums, so no Homework Template is shown >> [/color] I'm studying controlled rectifiers and for full wave bridge rectifiers the notes(that I'm studying from says) It says that the average load current is Id / 2 I don't understand how. Why...

Homework Statement Hello, the question is number 35 in this picture here: http://uploads.im/uEWAf.jpg It states, ''A suitable fuse rating for the mains supply has current rating - (A)10A (B)15A (C)30A (D)60AHomework Equations V = IR P = IV P = I^2 R P = V^2/R The Attempt at a Solution I...

Homework Statement A long straight wire of radius a and resistance per unit length R carries a constant current I. Find the Poynting vector N = E × H at the surface of the wire and give a sketch showing the directions of the current, the electric field E, the magnetic field H, and N. Integrate...

If you had a box made of mu-metal and and a magnetic material inside the box, then took an insulated wire and wrapped outside the mu-metal box and applied a current, then applied a magnetic field outside the box, which one would magnetize the mu-metal, even for a brief amount of time? Also, if...