Pickett's Charge

Examples of Pickett's Charge in the following topics:

• The Battle of Gettysburg

  • The main event was a dramatic infantry assault by 12,500 Confederates against the center of the Union line on Cemetery Ridge, known as Pickett's Charge.
  • The charge was repulsed by Union rifle and artillery fire at great losses to the Confederate army.

• Electric Field from a Point Charge

  • The electric field of a point charge is, like any electric field, a vector field that represents the effect that the point charge has on other charges around it.
  • If the charge is positive, as shown above, the electric field will be pointing in a positive radial direction from the charge q (away from the charge).
  • This means that because the charges are both positive and will repel one another, the force on the test charge points away from the original charge.
  • If the test charge were negative, the force felt on that charge would be:
  • The electric field of a positively charged particle points radially away from the charge.

• Static Electricity, Charge, and the Conservation of Charge

  • In both instances, charged particles will experience a force when in the presence of other charged matter.
  • The SI unit for charge is the Coulomb (C), which is approximately equal to $6.24\times 10^{18}$ elementary charges.
  • (An elementary charge is the magnitude of charge of a proton or electron. )
  • In physics, charge conservation is the principle that electric charge can neither be created nor destroyed.
  • The net quantity of electric charge, the amount of positive charge minus the amount of negative charge in the universe, is always conserved.

• Stress and Strain

  • The electric field of a point charge is, like any electric field, a vector field that represents the effect that the point charge has on other charges around it.
  • This means that because the charges are both positive and will repel one another, the force on the test charge points away from the original charge.
  • If the test charge were negative, the force felt on that charge would be
  • This makes sense because opposite charges attract and the force on the test charge will tend to push it toward the original positive charge creating the field.
  • The electric field of a positively charged particle points radially away from the charge.

• Conductors and Fields in Static Equilibrium

  • In the presence of charge or an electric field, the charges in a conductor will redistribute until they reach static equilibrium.
  • Conductors are materials in which charges can move freely.
  • If conductors are exposed to charge or an electric field, their internal charges will rearrange rapidly.
  • Negative charges in the conductor will align themselves towards the positive end of the electric field, leaving positive charges at the negative end of the field.
  • Describe behavior of charges in a conductor in the presence of charge or an electric field and under static equilibrium

• Induced Charge

  • Electrostatic induction is the redistribution of charges within an object that occurs as a reaction to the presence of a nearby charge.
  • Electrostatic induction is the redistribution of charge within an object, which occurs as a reaction to a nearby charge.
  • As such, it has no net charge.
  • In such an event, the electrons in the neutral object move (the protons are relatively inert) according to the charge of the nearby charged object (inductor).
  • Total charge is conserved, and that of the inductor decreases as it transfers charge to its subject.

• Equipotential Lines

  • Since they are located radially around a charged body, they are perpendicular to electric field lines, which extend radially from the center of a charged body.
  • For a single, isolated point charge, the formula for potential (V) is functionally dependent upon charge (Q) and inversely dependent upon radial distance from the charge (r):
  • Therefore, equipotential lines for a single point charge are circular, with the point charge at the center .
  • When multiple, discrete charges interact, their fields overlap.
  • At a point between the charges, a test charge may "feel" the effects of both charges.

• Charge Separation

  • Charge separation, often referred to as static electricity, is the building of space between particles of opposite charges.
  • All matter is composed of atoms made up of negatively-charged electrons and positively-charged protons.
  • Thus, the opposite charges attract.
  • Charge separation can be created not only by friction, but by pressure, heat, and other charges.
  • Charge separation occurs often in the natural world.

• Electric Field Lines: Multiple Charges

  • But what if another charge is introduced?
  • When modeling the electric fields of multiple charges, it's important to take into consideration the sign and magnitude of each charge.
  • This means that if charges q1 (with a +1 value) q2 (+2 charge) and q3 (+3 charge) are in the same field, one can connect 4, 8, and 12 field lines, respectively, to the charges.
  • Field lines should always point away from positive charges and towards negative charge.
  • Calculate the resultant force of the multiple electric charges on a test charge

• Electric Fields and Conductors

  • Electric fields are found around electric charges and help determine the direction and magnitude of force the charge exerts on a nearby charged particle.
  • Therefore, they can facilitate the flow of charge, or current.
  • There is no electric field inside a charged conductor.
  • A charged conductor at electrostatic equilibrium will contain charges only on its outer surface and will have no net electric field within itself.
  • This is because all the charges in such a conductor will symmetrically oppose other charges within the conductor, causing the net result to sum to 0.