Potential difference Definition and 701 Threads

Homework Statement What is the difference between E.M.F. and Potential Difference of a circuit? Homework Equations Both have similar SI unit, that is, Volt (V) The Attempt at a Solution I did find out one thing, that emf is the potential difference when there is no current flowing...

Consider a coaxial cable with inner radius a and outer radius b. The potential difference between the inner and outer conducter is V. How can it be shown that the electric field at a distance r from the inner conducter is given by: E = \frac{V}{r ln\frac{b}{a}} Any help would be much...

Homework Statement Consider a magnetron. It consists of an electron-emitting filament at the center of a cylindrical anode situated in a uniform magnetic field. Electrons of charge e and mass m are emitted with negligible velocity from the filament. What is the minimum potential...

Homework Statement For the RC Circuit (R = 1M Ohm, C = 1 Micro Farad and E = 30 V) find the potential difference across the resistor 10 sec after the switch is closed. Homework Equations V = E (1 - e^ -t/RC) The Attempt at a Solution I use the above equation but I get it wrong...

potential difference? Homework Statement picture shown in attachment The sliders are at the mid-point of the potential dividers. 1. Find the potential difference recorded by a digital voltmeter of infinite resistance connected as the voltmeter V in each circuit. 250/2 = 125...

I have done 1, i can't get the right answer for question 2. i seem to be getting minus7.5 volts. i know that's not anywhere near right because you can't get a minus voltage. i have tried many different ways to do this and i still can't get the right answer To get question 1 i used ohms law...

Homework Statement A small sphere with mass .015kg hangs by a thread between two parallel vertical plates .05m apart. The plates are insulating and have a uniform surface charge densities +σ and -σ. The charge on the sphere is q = 8.9 x 10^-6 C. What potential difference between the plates will...

we know the current flow only when there is a potential difference between two points.consider the point A and B in the file attached ,both A and B are at same potential then why the current flow between them

Homework Statement Electrons are accelerated from rest through a potential difference of 351 V. Then these electrons enter a uniform magnetic field that is perpendicular to the their initial directon. Due to the interaction with the magnetic field, they move in a circular path of radius...

Two parallel horizontal plates are 0.4 cm apart in air. An oil droplet of m = 4.9*10^-17 kg is introduced between the plates. If the drop has 2 electronic charges and if there is no air buoyancy, you can hold the droplet motionless between the plates if you keep the potential difference between...

Homework Statement Professor Milly Coulomb finds it takes 3.0 J of work to drag, at constant speed, a -9.0 mC charge between the plates of a parallel plate capacitor. (a) What is the work done by the electrical force in taking the charge between the plates? (b) What is the potential...

Homework Statement An isolated large-plate capacitor (not connected to anything) originally has a potential difference of 1030 volts with an air gap of 2 mm. Then a plastic slab 1 mm thick, with dielectric constant 5.1, is inserted into the middle of the air gap as shown in Figure 16.70. As...

Homework Statement The potential difference between the accelerating plates of a TV set is about 20 kV. If the distance between the plates is 1.0 cm, find the magnitude of the uniform electric field in the region between the plates. Homework Equations V=ED so E=V/D where E is the...

Homework Statement Through what potential difference would an electron need to be accelerated for it to achieve a speed of 5.8% of the speed of light (2.99792x10^8 m/s), starting from rest? Homework Equations E=Vq E=.5mv^2 The Attempt at a Solution Vq=.5mv^2 V=(.5mv^2)/q...

Homework Statement a certain parrallel plate capacitator has a plate separation d and a potential difference between the plates of V. If the electric field between the plates is uniform a) What is the strength of the electric field F Homework Equations Coloumbs Law F=k(q1q2/d^2)...

Homework Statement The 5.00-V battery in the figure ( http://session.masteringphysics.com/problemAsset/1009413/11/yf_Figure_26_42.jpg ) is removed from the circuit and replaced by a 20.00-V battery, with its negative terminal next to point b. The rest of the circuit is as shown in the figure...

Homework Statement The problems tells me to determine the potential difference between between two points. I alrady know that the potential of one point is zero. The problem I am having is that the cirucit has two batteries. I do not have a question so i will describe it, it hsould be easy...

What is the potential difference between two equal charge/line charge/ring charge? Is it zero everywhere, or only in middle of the two?

Homework Statement During a particular thunderstorm, the electric potential difference between a cloud and the ground is Vcloud-Vground = 1.3 X 10^8 V, with the cloud being at the higher potential. What is the change in an electron's electric potential energy when the electron moves from the...

I'm back again this week with a problem: A particle has a charge of +1.5 Micro Coulombs and moves from point A to point B, a distance of .20 m. The particle experiences a constant electric force, and its motion is along the line of action of the force. The difference between the particle's...

Homework Statement The work function of caesium is 1.35eV. A photoelectric cell has a caesium surface and is illuminated with monochromatic light of wavelength 400nm. What reverse potential difference must be applied to the tube to just stop a current passing through it? Homework Equations...

Homework Statement he electronic flash attachment for a camera contains a capacitor for storing the energy used to produce the flash. In one such unit, the potential difference between the plates of a 705 µF capacitor is 320 V. (a) Determine the energy that is used to produce the flash in...

Homework Statement A particle with a charge of -1.5 µC and a mass of 3.0 x 10-6 kg is released from rest at point A and accelerates toward point B, arriving there with a speed of 50 m/s. (a) What is the potential difference VB - VA between A and B? Homework Equations v=(square...

Just wondering how do you calculate the potential difference between Pt A and B in the picture. http://img370.imageshack.us/img370/5554/16004537xc8.th.jpg Value of E: 95 N/C AB=0.33 m the angle is 42 I researched and found an equation V= Ercostheta but I've never seen or used this...

Using your actual knowledge of the actual charge of an electron and the mass of an electron, determine he velocity of an electron that has been accelerated across a potential difference of 100000 volts. Please show me how to do this question. Thanks

Homework Statement A proton, initially at rest, is accelerated through an electric potential difference of 500V. What is the speed of the proton? Homework Equations V=k(q/r) Solving for r: r=k(q/v) v=d/t known charge of a proton: 1.6E-19C known value of k: 9E9Nm^2/C2 The...

1. A positive charged rod is held near, but does not touch a neutral electroscope. The charge on the knob becomes 1) positive and the leaves become positive 2) positive and the leaves become negative. 3) - and the leaves become + 4) - and the leaves become -. I chose 1), but it's wrong. I...

Homework Statement I am given a circuit wherein there is a capacitor C1 followed by a battery of PD E1 followed by a capacitor C2 followed by a battery of PD E2 connected back to C1. Find PD across C1 (v1) and C2 (v2) | _ E2_| C1 = = C2 |_E1_| Homework Equations...

Homework Statement There is no problem but I am trying to understand the definition of 'electrical potential.' What is it. What is electrical potential difference. It is the amount of work needed to move a charge from point A to point B divided by the magnitude of the charge. What is...

Homework Statement How would we find the potential difference given the frequency of the incident light and the kenetic energy of an the emitted electrons? Homework Equations E= hf-W V= w/q e= 1.602*10^-19 The Attempt at a Solution Given: f= 7.4*10^15 Hz KE= 1.9eV...

Homework Statement A small sphere with mass 1.50g hangs by a thread between two parallel vertical plates 5cm apart. THe plates are insulating ahnd have uniform surface charge densities + and - \sigma. The charge on the shpere is q = 8.90 x 10^-6 C. What potential difference between the...

Homework Statement Question: an electron with a velocity of 5.0x10^{}6 m/s is injected into a parallel plate apparatus through a hole in the positive plate. it moves across the vacuum between the plates. what would the potential difference have to be in order to stop the electron 25% of the...

Homework Statement http://img152.imageshack.us/img152/696/1005200802ps4.png The wire XY in the circuit is made of a material of high resistivity and uniform area of cross-section. What is the potential difference between X and 65cm mark in the circuit? Homework Equations The Attempt at a...

Homework Statement http://img241.imageshack.us/img241/1087/09052008hf9.png What is the potential difference across (i) AB (ii) BC. Homework Equations ?? The Attempt at a Solution (i) \frac{200}{400} \times 6 = 3V Is this right? :confused:

Homework Statement A force of .053 N is required to move a charge of 37 microCoulombs a distance of .25m in an electric field. What is the size of the electric potential difference between the two points? Homework Equations ? The Attempt at a Solution I'm really stuck...

[SOLVED] Average Potential Difference Homework Statement The voltage across the terminals of an ac power supply varies with time according to V=V_0\cos(\omega t). The voltage amplitude is V_0 = 46.0 V From the prior question, I already figured out that the root-mean-square potential...

1. Through what potential difference (\DeltaV) would you need to accelerate an alpha particle, starting from rest, so that it will just reach the surface of a 15 x 10^(-15) m ^{238}U nucleus? 2. KE = q\DeltaV E = \gamma_{p}mc² r = \frac{mv}{qB} 3. Ok, I feel like I am close to what I really need...

Using a Van De Graaff (VDG) machine, we can easily generate million-volt high voltage. The high potential difference can be generated effectively with minimum energy supplied to the machine. The larger the volume of the machine would be, the higher the voltage could get. However, stability...

Homework Statement Find the potential difference of point b relative to point a. Homework Equations The Attempt at a Solution I found out that E1 = 18V and E2 = 7V but I don't know where to go from there.

1) You have a potential difference of 6 volts. How much work is done to transfer .19 coulombs of charge through it? Answer in units of Jules. 2) Through what potential difference would an electron need to be accelerated for it to achieve a speed of 6% of the speed of light(2.99792e8)...

1) You have a potential difference of 6 volts. How much work is done to transfer .19 coulombs of charge through it? Answer in units of Jules. 2) Through what potential difference would an electron need to be accelerated for it to achieve a speed of 6% of the speed of light(2.99792e8)...

Hi anyone can solve this problem? A volume charge density of pv= 1/r^2 uC/m^3 exists in the region bounded by 1.0m < r < 1.5m. Find the potential difference between the point A(3.0, 4.0, 12.0) and the point B (2.0, 2.0, 2.0). Anyone can show me the solution for this problem?

Homework Statement I really need help with this problem. The question is: Each side of an equilateral triangle measures 3.61cm. A charge of -0.34mC is placed at each vertex. what is the potential difference at the midpoint of the base of the triangle? Homework Equations V=kq/r [b]3...

I am stuck on this question about potential difference, the question is: each side of an equilateral triangle measures 3.61cm. A charge of -0.34mC is placed at each vertex. what is the potential difference at the midpoint of the base of the triangle, i need quick help. Thank you.

Homework Statement (a) Determine the capacitance of a Teflon-filled parallel-plate capacitor having a plate area of 1.90 cm2 and insulation thickness of 0.0600 mm. (b) Determine the maximum potential difference that can be applied to the capacitor. kV Homework Equations I THOUGHT C =...

The question is to calculate the speed of a proton that is accelerated from rest through a potential difference of 120V. Qp(charge of proton) ~ 1.60E-19C...with this, DeltaU = Qp*DeltaV...in which DeltaU is positive. It makes sense since the proton is heading towards a higher electric...

Homework Statement Six identical capacitors with capacitance C are connected as shown in figure 30.68 (attachment). What is the potential difference between points a and b? Homework Equations C=Q/V The Attempt at a Solution The Cequivalent = 3/2 C Therefore, Q = CV...

Homework Statement The radiation detector known as a Geiger Counter uses a closed hollow cylindrical tube with an insulated wire along its axis. Suppose a Geiger tube as its called has a 1.0mm diameter wire in a tube with a 25mm inner diameter. The tube is filled with a low pressure gas whose...

Homework Statement On attachment. Part B only. I got C. Homework Equations mass of proton is 1.673*10^-27 q0 = 1.60*10^-19 The Attempt at a Solution For part B I thought I could divide the intial speed by 2 and plug it back into the energy conservation equation: .5mv^2 + q0V1...

Homework Statement Figure 16.69 A thin spherical shell made of plastic carries a uniformly distributed negative charge -7e-10 coulombs (indicated as -Q1 in the diagram). Two large thin disks made of glass carry uniformly distributed positive and negative charges 1.7e-05 coulombs and...