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Electric potential

1) Please refer attachment. 2) What are (a) the charge and (b) the charge density on the surface of a conducting sphere of radius 0.15m whose potential is 200V ( with V = 0 at infinity)?

Electric field of Plastic Pipes

A plastic pipe has an inner radius of a = 31.00 cm and an outer radius of b = 68.00 cm. Electric charge is uniformly distributed over the region a < r < b. The charge density in this region is 42.00 C/m3. Calculate the magnitude of the electric field at r = 0.29 m. Calculate the magnitude of the electric field at r = 0.57 m. C

Electrostatic Charges of Isolated Spheres

Conducting Spheres Problem 4. Identical isolated conducting spheres 1 and 2 have equal charges and are separated by a distance that is large compared with their diameters (a). The electrostatic force acting on sphere 2 due to sphere 1 is F. Suppose now that a third identical sphere 3, having an insulated handle and initi

Electron potential of spherical conductor

Find the electron potential inside and outside of a spherical conductor of radius R = 15 cm carrying a charge Q = 10^-9 C. Evaluate your results for f = 5 cm and r = 20 cm, assuming V = 0 at infinity. Sketch the potential as a function of r. What is the capacitance of the conducting sphere?

Electric field of a charge inside hollow conducting sphere

(See attached file for full problem description) A hollow grounded conducting sphere of radius a contains a point charge Q at the radius b as shown in the figure (see attachment) a) Show that the field inside the sphere is the same as if there were no sphere and, instead, a charge Q' = -(a/b)Q at D = (a/b)a. You can prov

Point charge above a conducting plate

A point charge Q lies at a distance D above a large grounded conducting plate. a) Calculate the surface charge density induced on the plate as a function of the radius r from the foot of the perpendicular drawn from the charge. b) Show that the total induced charge is -Q.

Electric Potential Difference Magnitude and Sign

Location A is 3.00 m to the right of a point charge q. Location B lies on the same line and is 4.00 m to the right of the charge. The potential difference between the two locations is Vb-Va= 45.0 V. What is the magnitude and sign of the charge?

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)