What is Charged object: Definition and 19 Discussions

Electric charge is the physical property of matter that causes it to experience a force when placed in an electromagnetic field. There are two types of electric charge: positive and negative (commonly carried by protons and electrons respectively). Like charges repel each other and unlike charges attract each other. An object with an absence of net charge is referred to as neutral. Early knowledge of how charged substances interact is now called classical electrodynamics, and is still accurate for problems that do not require consideration of quantum effects.
Electric charge is a conserved property; the net charge of an isolated system, the amount of positive charge minus the amount of negative charge, cannot change. Electric charge is carried by subatomic particles. In ordinary matter, negative charge is carried by electrons, and positive charge is carried by the protons in the nuclei of atoms. If there are more electrons than protons in a piece of matter, it will have a negative charge, if there are fewer it will have a positive charge, and if there are equal numbers it will be neutral. Charge is quantized; it comes in integer multiples of individual small units called the elementary charge, e, about 1.602×10−19 coulombs, which is the smallest charge which can exist freely (particles called quarks have smaller charges, multiples of 1/3e, but they are only found in combination, and always combine to form particles with integer charge). The proton has a charge of +e, and the electron has a charge of −e.
Electric charges produce electric fields. A moving charge also produces a magnetic field. The interaction of electric charges with an electromagnetic field (combination of electric and magnetic fields) is the source of the electromagnetic (or Lorentz) force, which is one of the four fundamental forces in physics. The study of photon-mediated interactions among charged particles is called quantum electrodynamics.The SI derived unit of electric charge is the coulomb (C) named after French physicist Charles-Augustin de Coulomb. In electrical engineering it is also common to use the ampere-hour (Ah). In physics and chemistry it is common to use the elementary charge (e as a unit). Chemistry also uses the Faraday constant as the charge on a mole of electrons. The lowercase symbol q often denotes charge.

View More On Wikipedia.org
  1. J

    Elevated Geiger Counter Radiation Reading for Envelope?

    I previously purchased a Geiger counter (GQ Electronics GMC-600+) for a university lab and have been confused about an elevated radiation reading from the envelope the Geiger counter came in. The envelope was a USPS Priority Mail bubble mailer envelope...
  2. J

    Can a neutral insulator be attracted to a charged object?

    Homework Statement Hi all. I'm a teacher and one of my students asked me a question I couldn't answer today. It's a multiple choice question: A neutral object is attracted to an electrically charged rod. The two are not touching. The neutral object: A. is a conductor B. is an insulator C...
  3. Z

    Angle between 2 charged spheres hanging from string

    Homework Statement Two positively charged metal spheres are suspended from the same hook by light strings of equal length, making an angle of 10.0◦ with each other. The charges carried by the spheres are as shown in the diagram. After that, the spheres are brought in contact briefly, then...
  4. EM da Costa

    Calculate work done on charged object between plates

    Homework Statement I am trying to calculate the theoretical time that it takes for a small piece of aluminium foil on a bottom plate to reach a top plate. The plates have a potential difference created by a 3kV Cockcroft–Walton generator. The plates are short cylinders with a surface area of...
  5. hackhard

    Can Wood Be Used as a Capacitive Sensor in an LM358 Op-Amp Circuit?

    i connected pin 4 and 8 to gnd and +5 v respectively .when pin 2 touches wood, or hand pin 1 is high. i understand skin is capacitive , but wood?
  6. A

    When a charged object is brought close to an uncharged one (attraction)

    I have always been told that a charged object will attract an uncharged on when brought close (but do not touch) the uncharged object. However, wouldn't this depend on whether the uncharged object is an insulator or an conductor? This is my reasoning, but I am not sure if it is correct: When...
  7. S

    How does a magnetic field affect an electrical field

    More specifically, what happens and why when a magnet is brought close to a nonferrous charged object.
  8. A

    Finding the distance traveled by a charged object

    There are two electrically charged objects that are placed 6 cm away from each other. Each object has an electrical charge of +1 microColoumbs and a mass of 1 milligram. If one object is fixed in place, how far does the other go in 2 milliseconds? So I'm given the charge, distance between the...
  9. G

    Water bends when charged object is near

    Homework Statement Why is it that when a charged object is near a stream of water (polar), it causes the stream to bend towards the object (attraction) instead of bend away (repulsion)? I know why the water bends, but why does it not REPEL instead? Homework Equations N/A just an...
  10. S

    Electrically Charged object

    If I have a charged object in contact with normal air (but nothing else) and insulated, does it lose charge over time? Does the answer depend on the object being an conductor or an insulator itself?
  11. K

    Voltage on a positively charged object?

    If I charge a van de graaff to say 10,000 V I would think of the voltage as electric pressure. There would be so many electrons looking to escape the metal ball, and this overcrowding of the electrons (electrostatic forces) would create electric pressure, or voltage. If my analogy is off, then...
  12. P

    Suspended Charged Object in Uniform Electric Field

    Homework Statement A charged cork ball of mass m is suspended on a light string in the presence of a uniform electric field, as shown in the figure below. When E = (A + B) N/C, where A and B are positive numbers, the ball is in equilibrium at the angle θ. (a) Find the charge on the ball...
  13. D

    Human body grounding a charged object

    In a very good book, Chabay and Sherwood explain that when an initially uncharged person touches a negatively charged metal object, free electrons from the metal neutralize some Na+ ions in the salty layer on the person's skin. The person then becomes negatively charged and the neutral Na atoms...
  14. M

    Speed of a charged object accelerated through a potential difference

    Homework Statement A 5.0 g object carries a net charge of 3.8uC. It acquires a speed v when accelerated from rest through a potential difference V. A 2.0 g object acquires twice the speed under the same circumstances. What is its charge? Homework Equations The Attempt at a...
  15. I

    Electric field direction and hovering charged object

    Homework Statement A small object of mass 3.64 g and charge -18.1 µC is suspended motionless above the ground when immersed in a uniform electric field perpendicular to the ground. What are the magnitude and direction of the electric field? Homework Equations E=F/q The Attempt at...
  16. F

    What is the maximum charge that can be put on a charged aluminum sphere?

    I am doing some conceptual design, and was hoping to be able to get some answers here before I devote too much time to this. I would like to be able to charge a piece of aluminum so that it holds a charge (negative) of 8 Coulombs. I was hoping to achieve this with something similar to a van...
  17. Y

    How to draw electric field around neutral object, dipole, and charged object

    Homework Statement I'm working on a homework problem which requires me to roughly sketch electric field lines. The object on the left is neutral and grounded, the object on the right was just struck by lightning (and therefore very negatively charged) and I assume that the neutral object in...
  18. S

    How Does Charge Affect Motion and Force in Physics Problems?

    If a charged object experiences say, an attractive force, as it moves closer to the other charged object doesn't the force increase.. so how can you ever have uniform acceleration with moving charged objects? can't it only be instantaneous acceleration? how can you apply the kinematics equations...
  19. B

    Force on a Charged Object in a Field

    A charge of q = +7.55 μC is located in an electric field. The x and y components of the electric field at this point are Ex = 6.14E+3 N/C and Ey = 8.17E+3 N/C, respectively. What is the magnitude of the force on the charge? i know for sure that i am going in the wrong direction in this one...