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Charge

An electric charge is the physical property of matter that causes it to experience a force when closed to other electrically charged matter. There are two types of electric charges, positive and negative. Positively charged substances are repelled from other positively charged substances, but are attracted to negatively charged substances. Similarly, negatively charged substances are repelled from negative and attracted to positive. A substance will be negatively charged if it has an excess of electrons and will otherwise by positively charged or uncharged. The SI unit for electric charge is a coulomb (C).

The electric charge is a fundamental conserved property of some subatomic particle, which determines their electromagnetic interaction. Electrically charged matter is influenced by and will produce electromagnetic fields. This interaction between a moving charge and an electromagnetic field is the source of the electromagnetic force. The electromagnetic force is one of the four fundamental forces.

The charge of an electron is -1 and the charge of a proton is +1. Coulomb’s law quantifies the electrostatic force between two particles by asserting that the force is proportional to the product of their charges and inversely proportional to the square of the distance between them.

The charge of an antiparticle is equal to the corresponding particle but with an opposite sign. Quarks have fractional charges of either -1/3 or +2/3. Free standing quarks have never been observed.

An ion is an atom which has lost at least one electron. This would give it a net positive charge (cation) or has grained at least one electron, giving it a net negative charge (anion). Monatomic ions are formed from single atoms. Polyatomic ions are formed from two or more atoms that have bonded together. Each case yields an ion with a positive or negative net charge. 

Categories within Charge

Coulomb's Law

Postings: 81

Coulomb's law is the inverse-square law describing the electrostatic interaction between electrically charged particles.

Physics: Electric Fields and Positive Charges

See the attached file. 1. In a radical system the electric potential is given by the function V(r)=k(1/r2 - 1/r) Where k is constant and r is the radical distance. a. Find the electric field as a function of distance. b. If a positive charge was released in this system, at what radius would it be at equilibrium (i.e

Processes of a Neuron

I need help in explaining the process a neuron undergoes when going from a resting potential to an action potential to the release of its neurotransmitters. I am not too sure how to approach this because I do not really understand the process myself.

Electrostatic Field and Potential in Spheres

1. The electrostatic field E in a particular region can be expressed in terms of spherical coordinates. Derive an expression for the potential difference. 2. The electrostatic potential in a region is given by a function. Derive an expression for the electrostatic field in this region, and hence determine the field at the poi

Motion of charged particle in uniform electric & magnetic fields

In this question we will consider the motion of a charged particle in uniform electric and magnetic fields that are perpendicular. You may ignore the effects of gravity throughout this question. (a)(i) Consider a charged particle of mass m and charge q that is moving in a uniform electric field E = Ee_y and a perpendicular u

A whistle-blower in her allegations made in a qui tam suit, alleged that her former employer fired her because she told the company that it was "padding the bills" to the federal government for the cost-plus contract it had to build ejection seats for fighter aircraft. She alleges that the company overcharged for materials, ran up labor costs, threw "all kinds of stuff in overhead," and illegally plugged corporate administrative costs into the contract billings. As the forensic accountant hired by the U.S. Justice Department to litigate this case, answer the following: a. What documents will you seek during discovery to address the whistle-blower's allegations? b. What will you be looking for in each of the requested documents? c. What will be the basis/foundation for the opinions you will provide in this case? d. How will you utilize the whistle blower in pursuing your opinions in this case? Exercise 11-19: Jamestown Electric has a contract with an agency of the federal government to provide electrical power to the agency for a five-year period. The contract stipulates, in part, that the power will be provided "at the lowest reasonable cost without compromising safety." In connection with this contract, Jamestown Electric buys and uses coal from its wholly-owned subsidiary Great Plains Coal Company. The sale of this coal to Jamestown Electric specifically for this contract represents 40 percent of the coal sales for Great Plains. The profit for Great Plains Coal Company during the life of the contract averaged $1.2 million per year. Jed Jones, a former employee of Jamestown Electric was fired by the firm and immediately filed a qui tam suit alleging Jamestown had intentionally overcharged the government throughout the life of the power supply agreement a. You are the forensic accountant for the whistle-blower's attorney. What are the accounting issues in this case? What are the damages in this case? What documents and other information do you intend to seek? What is the basis for your opinion? b. You are the forensic accountant for Jamestown Electric. What are the accounting issues in this case? What are the damages in this case? What documents and other information do you intend to seek? What is the basis for your opinion? Exercise 11-20: Up North Marina is and has been the only marina on Lake Woodward for the last 20 years. There have been numerous efforts to open other marinas during this time period. Each attempt, however, was unsuccessful. A recent lawsuit was successful in proving liability on the part of Up North Marina management is keeping many of those other marina operations off the lake. The court is now addressing the liability issue in this case. a. You are the forensic accountant for the plaintiffs in the case. What documents and other information will you seek to compute damages? What will be the basis for you damage estimate? What is your theory of damages, and what are the components of your damage model? b. You are the forensic accountant for the defendant in the case. What documents and other information will you seek to compute damages? What will be the basis for your damage estimate? What is your theory of damages, and what are the components of your damage model? What are your plans to counter the plaintiffs' damage calculations?

Exercise11-18: A whistle-blower in her allegations made in a qui tam suit, alleged that her former employer fired her because she told the company that it was "padding the bills" to the federal government for the cost-plus contract it had to build ejection seats for fighter aircraft. She alleges that the company overcharged for

Physics: Drift speed of electrons in wire; electric field in wire

1. Two wires both carry the same current (I). The moving charged particles in both wires are electrons, but the concentration of moving electrons in wire #1 is double the concentration of moving electrons in wire #2. Under what circumstances will the drift speed of electrons be the same in both wires? Choose the answer that b

Simple Research Paper

Title: How To Bend Water with Static Electricity Need simple Purpose Simple Hypothesis Material and Procedure Used Research Information to include: Introduction, Body, and Conclusion Introduction should restate your questions, and summerize the purpose of the experiment. It should also identify the scientific concep

Magnetic field due to electric current

A straight wire is carrying current along the x-axis in the +x direction. A second straight wire is carrying an equal current along the y-axis in the +y direction. Both of the wires are in the x-y plane, and all questions pertain only to the magnetic field at points in the x-y plane. Which of the following statements are true ab

NASA tele-transporter, magnetic field direction, generator, motor

1. Two test charges suspended in vacuum attract each other with a force of 1x10-6 N. What will the attractive force be if the vacuum is replaced with water at 20o C? The permittivity of water at this temperature is 7.07x10-10 C2/N-m2. 2. Three test charges, each with a charge of +1x10-6 C, are located at the points of an eq

Physics: Three charges on a line, find direction and magnitude of net force

Part 1 Three charges, Q1, Q2, and Q3 are located in a straight line. The position of Q2 is 0.235 m to the right of Q1. Q3 is located 0.125 m to the right of Q2. The force on Q2 due to its interaction with Q3 is directed to the..... Right if the two charges are negative. A: True B: False Right if the two charges have o

Capacitance, charge, area related physics questions

1) A capacitor has a charge of 0.002C when it is connected across a 100V battery, Find its capacitance. 2) A capacitor has a capacitance of 6.40uF. How much charge must be removed to lower the potential difference of its plate by 50.0V? 3) The plates of a parallel-plate capacitor have areas of 40cm2 and are separated by 0.2mm

Physics Electric ForceFour questions regarding the Coulomb's law are answered. In all question, a point charge is placed together with one (or two) other point charges in a straight line. The resulting electric force is found.

The answers are given, but no workings. *I only need solutions for these * 1. What is the magnitude of the force on a change of +2 x 10-7C that is 0.3m from a charge of -5 x 10-7C? Answer: 10-2N attractive force. 2. Two electrons repel each other with a force of 10-8N. How far apart are they? Answer: 1.5 x 10-10m 3

Phyical science Book Bill W.Tillery 8th edition

1. An inflated rubber balloon is rubbed with a wool cloth until an excess of a billon electrons is on the ballon. What is the magnitute of the charge on the ballon? 2. what is the force between two ballons with a negative charge of 1.6x10-10c if the ballon s are 5.0cm apart? 3. How much entergy is avalible from a 12V stor

Financial Reporting

Use a copy of the most recent annual report for General Electric. Then, use the information contained in the balance sheet and the income statement to answer the questions below in addition to discussing the changes in the dollar amounts reported in the current annual reporting period as compared to the previous annual reporting

Find the Speed of a Charged Particle

A small particle has charge -6.90 micro-Coulombs and mass 1.00×10-4 kg . It moves from point A, where the electric potential is VA= 280 V , to point B, where the electric potential is VB= 930 V; note that this is greater than the potential at point A. The electric force is the only force acting on the particle. The particle

Electric field due to coaxial cable

A long coaxial cable consists of an inner cylindrical conductor with radius a and an outer coaxial cylinder with inner radius b and outer radius c. The outer cylinder is mounted on insulating supports and has no net charge. The inner cylinder has a uniform positive charge per unit length lambda. Calculate the magnitude of th

The motion of a particle in uniform electric and magnetic fields

Full question is attached. 1) In this question we will consider the motion of a charged particle in uniform electric and magnetic fields that are perpendicular. You may ignore the effects of gravity throughout this question. a) i) Consider a charged particle of mass m and charge q which is moving in a uniform electric field

Organic Structures: Polarity and Electron-Dot Formulas

Please see the attachment for a better formatting of these questions. 1) Draw a structural formula for each of the following molecules. Which bonds are polar? Indicate the polarity by proper placement of the symbols d+ and d-. a. CH3Cl b. H2 2) Draw structural formulas for all possible isomers having the following mole

Phenomena of charging due to transfer of charge and induction.

(Please see the attached file) 6) a) I placed several aluminum pie plates on top of the large metal sphere of the van de Graaff machine and then turned it on. After a few seconds the pie plates flew off. Explain why. Focus on physics involved. b) When I placed packing peanuts in a pie plate they also flew off. Why? Can t

Electron Relative to the Point Charge Based on Electric Force

A point charge q = -3.5 x 10-10 C is fixed at the origin, as shown below. Where must an electron be placed relative to the point charge so that the electric force acting on the electron is exactly opposite to its own weight? Include a sketch showing the position of the charges (it does not need to be to scale, but it must show c

charge required to break the ring due to electrostatic repulsion

1. Consider a conducting ring made of thin wire wheel: d is the diameter of the wire and D is the diameter of the ring (D>>d). A charge Q placed on the ring is just enough to cause the ring to break apart due to electrostatic repulsion. All linear dimensions are doubled (multiplied by 2); what is the new charge required

We have a disk of radius R and uniform surface charge density A shown below.

Please see the attached file. We have a disk of radius R and uniform surface charge density A shown below. a) What is the potential with respect to infinity at a distance Z above the center of this disk? b) If A equals 9 pC/m^2 and R = 4m what is the potential at the point Z = 3m in V c) What is the electric field at Z=3m

Electrostatics - Writing an Expression for Volume Charge Density

A) Write an expression for the volume charge density, rho(r) of a point charge q at r' (the volume integral of rho(r) = q) b) What is the volume charge density of an electric dipole consisting of a point charge-q at the origin and a point charge +q at a(bar) c) What is the charge density of a uniform infinitesimally t

Repulsive Forces Between Charges

A repulsive force force of 220 N exists between an unknown charge and a charge of +4.7mC. If they are separated by 2.5cm, what is the magnitude of the unknown charge?

Electric Potential

The membrane that surrounds a certain type of living cell has a surface area of 5.0 10-9 m2 and a thickness of 1 10-8 m. Assume that the membrane behaves like a parallel plate capacitor and has a dielectric constant of 5. (a) If the potential on the outer surface of the membrane is +70.0 mV greater than that on the inside s