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metallic and electrically neutral

Object A is metallic and electrically neutral. It is charged by induction so that it acquires a charge of -3.0 x 10^-6 C. Object B is identical to object A and is also electrically neutral. It is charged by induction so that it acquires a charge of +3.0 x 10^-6 C. What is the difference in mass between the charged objects an

Physics Questions (Multiple Choice)

Question 1: If there is a force of 5.0 x 10-12 N acting to the left on an electron, the electric field intensity at the location of this electron will be: a. zero. b. 8.0 x 10-31 N/C to the left c. 3.1 x 107 N/C to the left d. 3.1 x 107 N/C to the right e. none of these Question 2: In one mole or 18 grams of

Economies of Scope/Logistics/Break Even

9. (a) What is the meaning of economies of scope? How do they differ from economies of scale? (b) What do learning curves show? How do they differ from economies of scale? What is the usefulness of learning curves as a managerial tool? What is the reason for rising international trade in inputs and the use of foreign trade in in

Find the probability that they meet again after N steps.

This is from Reif's Statistical and Thermal Physics: Two drunks start out together at the origin, each having equal probability of making a step to the left or right along the x-axis. Find the probability that they meet again after N steps. It is to be understood that the men make their steps simultaneously. (It may be helpf

electric field along central axis of uniformly charged ring

Charge is uniformly distributed around a ring of radius R= 2.40 cm and the resulting electric field magnitude E is measured along the ring's central axis ( perpendicular to the plane of the ring). At what distance from the ring's center is E maximum? In this question, I end up with E(total) = (q * z) / 4*Pi * e * (R^2 + z^2)

Defibrillator problem

A defibrillator passes 18 A of current through a persons torso in 2.0 ms. 1) How much charge moves during this time? 2) How many electrons pass through the wires connected to the patient?

Electricity and Magnetism (Ampere's Law)

1. The long, straight wire AB shown in Figure (Please see the attached file) carries a current of 14 A. The rectangular loop whose long edges are parallel to the wire carries a current of 5 A. Find the magnitude and direction of the net force exerted on the loop by the magnetic field of the wire. 2. A long straight solid cyli

Electric Field and Potential

Positive charge, Q, is distributed evenly along the y-axis between y=0 and y=a. A negative charge, -q is located on the x-axis a distance x from the rod. (a) Find the electric field at the location of the negative charge. (b) Find the potential at the location of the negative charge. (see attached file for diagram)

Force between a point charge and conducting sphere

Using method of images, find the force of attraction between an external point charge +Q and a conducting sphere of potential V_0. Take the charge to be a distance D from the center of the sphere. What value of V_0 makes the force equal 0?

Method of images.

Consider a point charge +q at a distance d above an infinite grounded conducting plane. (a) Determine the charge density induced on the surface, then integrate to find the total surface charge. (b) Find the force that the point charge exerts on the conductor by considering the force on the induced surface charge densi

Optic: Polarization

Light is send through the two-sheet polarizing system with unknown orientation of the polarizing axes (see attachment). If the ratio of the emerging intensity to the initial intensity is 0.7, is the light initially polarized or not? Prove your answer. Please state what equations you use (if any).

Charges and Electric Field Problems

1. Suppose 4 equal positive charges +Q are arranged in a square as shown in the attached diagram. An "x" marks positions A, B, and C. Draw arrows showing the direction of the electric field at each of those points. (If the field strength is zero at a point, say so.) 2. Now we have 4 charges of equal magnitude, but 2 are posi

Electric Charge

Find the total electric charge of 1 kg of (a) electrons and (b) protons.

Electric Charge

When adhesive tape is pulled from a dispenser, the detached tape acquires a positive charge and the remaining tape in the dispenser acquires a negative charge. If the tape pulled from the dispenser has 0.14 micro C of charge per centimeter, what length of the tape must be pulled to transfer 1.8 x 10^13 electrons to the remaing

Electric Field, Sphere Potential and Potential Energy of System

Please solve step-by-step as simply as possible. Questions: a) Find the potential energy of the system of 3 charges. b) What is the dipole moment of this dipole ____ given these 2 vectors. c) Now place answer b) in an electric field. d) What is this field ____ . e) What is the force on ____ . Please see the attached

Sphere of charge

Please solve step by step as simply as possible. The teacher gave this info out, but I can't make sense of it. I don't think it's even right - is it? See the attached file for diagrams. Questions: (a) what is the electric field ... (b) what is the field before and the field after A touches B (c) B touched to A, then pl

PE of particles

Please show all work and show all equations used and diagrams, etc. etc. so I understand completely please. 1) A particle with charge 5.5*10^-8C is fixed at the origin. A particle with a charge -2.3*10-8C charge is moved from X=3.5cm on the x axis to y=3.5cm on the y axis. The change in PE of the two charge system is: 2)


1) 10 Coulombs of charge are placed on a spherical conducting shell. A particle with a -3C point charge is placed at the center of the cavity. The net charge in coulombs on the inner surface of the shell is what? 2) A 30 N/C uniform electric field points perpendicularly towards the left face of a large neutral conducting shee

Dealing with Charge/gaussian

1) A physics instructor in an antennae room charges an electrostatic generator to 25 microC, then carries it into the lecture hall. The net electric flux in N.m^2/C through the lecture hall walls is what? 2) A point particle with charge q is at the center of a Gaussian surface in the form of a cube. The electric flux through


Please show all work and diagrams plus equations used to solve problem. Thanks! Two point particles, with charges of q1 and q1 are placed a distance r apart. The electric field is zero at a point P between the particles on the line segment connecting them. We conclude that: (answer C - why) a) q1 and q2 must have the sa

Electrostatic Force Calculations

Please show all work and diagrams plus equations used to solve problem. Thanks! 1) Two identical conducting spheres A and B carry equal charge. They are separated by a distance much larger than their diameters. A third identical conducting sphere C is uncharged. SPhere C is first touched to A, then to B, and finally remov

Charge problems

Please give step by step solutions without skipping details to solve and give the answers please! QUESTION GIVEN: 1) In the figure, a central particle of charge -q is surrounded by two circular rings of charged particles. What are the magnitude and direction of the net electrostatic force on the central particle due to th

Charge on Amber

Two small charged pieces of amber experience a force when they are separted by a distance R. If the charge on each of the bodies is tripled and the separation between them is halved, what is the ratio of the new force to the original force between them?

Electric Potential and Four Point Charges

Four point charges q = +3.6 uC are arranged in a square of edge length 2.0 cm. What is the electric potential at the center of the square? What is the electric potential at the midpoint of one edge?

Density of Fluids

The fluid in a lead storage battery for a car has a specific gravity of 1.30, when it's fully charged and 1.15 when it's discharged. By how much does the density of the fluid change when the battery is completely run down?

Electric Field for a Spherical Shell

A spherical shell with inner radius a and outer radius b has a total charge Q distributed uniformly throughout its volume with a charge density p. Calculate the resulting electric field for r < a, a < r < b, and b < r.

Electric Charge and Direction of Force

Four point charges with magnitude 5.0 uC are placed at the corners of a square that is 30 cm on a side. Two charges, diagonally opposites each other, are positive, and the other two are negative. What are the magnitude and the direction of the force on one of the charges?