electrostatic force

Examples of electrostatic force in the following topics:

• Nuclear Fusion

  • A substantial energy barrier of electrostatic forces must be overcome before fusion can occur.
  • At large distances, two nuclei repel one another because of the repulsive electrostatic force between their positively charged protons.
  • The electrostatic energy per nucleon increases without limit as nuclei get larger due to the electrostatic force.
  • At nucleus radii distances, the attractive nuclear force is stronger than the repulsive electrostatic force.
  • Describe the electrostatic and strong nuclear forces and how they act to oppose or promote a fusion reaction

• Spherical Distribution of Charge

  • The charge distribution around a molecule is spherical in nature, and creates a sort of electrostatic "cloud" around the molecule.
  • Through the work of scientists in the late 18th century, the main features of the electrostatic force—the existence of two types of charge, the observation that like charges repel, unlike charges attract, and the decrease of force with distance—were eventually refined, and expressed as a mathematical formula.
  • The mathematical formula for the electrostatic force is called Coulomb's law after the French physicist Charles Coulomb (1736–1806), who performed experiments and first proposed a formula to calculate it.
  • This distribution around a charged molecule is spherical in nature, and creates a sort of electrostatic "cloud" around the molecule.
  • It is more easily affected by electrostatic forces than molecules with uniform charge distributions.

• Nuclear Stability

  • An isotope's nuclear stability depends on the balance of electric and nuclear forces between its protons and neutrons and their arrangement.
  • The protons, which are both positively charged, repel one another through electrostatic force.
  • This force is offset by the nuclear force, which attracts protons and neutrons.
  • This is because, for any constant number of protons, the difference between nuclear force and electrostatic repulsion of protons increases with increasing neutron count.
  • Identify the fundamental forces which lead to stability and/or instability of atomic nuclei

• Stress and Strain

  • The effect is felt as a force and when charged particles are not in motion this force is known as the electrostatic force.
  • The electrostatic force is, much like gravity, a force that acts at a distance.
  • The thing to keep in mind is that the force above is acting on the test charge Q, in the positive radial direction as defined by the original charge q.
  • 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

• Electric Field from a Point Charge

  • The effect is felt as a force, and when charged particles are not in motion, this force is known as the electrostatic force.
  • The electrostatic force is, much like gravity, a force that acts at a distance.
  • The thing to keep in mind is that the force above is acting on the test charge Q, in the positive radial direction as defined by the original charge q.
  • 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:

• Superposition of Forces

  • The superposition principle (superposition property) states that for all linear forces the total force is a vector sum of individual forces.
  • Therefore, the principle suggests that total force is a vector sum of individual forces.
  • The scalar form of Coulomb's Law relates the magnitude and sign of the electrostatic force F, acting simultaneously on two point charges q1 and q2:
  • For example, when a charge is moving in the presence of a magnetic field as well as an electric field, the charge will feel both electrostatic and magnetic forces.
  • Total force, affecting the motion of the charge, will be the vector sum of the two forces.

• Dipole-Dipole Force

  • These forces are weak compared to the intramolecular forces, such as the covalent or ionic bonds between atoms in a molecule.
  • Dipole-dipole forces: electrostatic interactions of permanent dipoles in molecules; includes hydrogen bonding.
  • Ion-dipole forces: electrostatic interaction involving a partially charged dipole of one molecule and a fully charged ion.
  • Instantaneous dipole-induced dipole forces or London dispersion forces: forces caused by correlated movements of the electrons in interacting molecules, which are the weakest of intermolecular forces and are categorized as van der Waals forces.
  • Dipole-dipole interactions are electrostatic interactions between the permanent dipoles of different molecules.

• Introduction to Intermolecular Forces

  • This attractive force has its origin in the electrostatic attraction of the electrons of one molecule or atom for the nuclei of another.
  • If there were no van der Waals forces, all matter would exist in a gaseous state, and life as we know it would not be possible.
  • It should be noted that there are also smaller repulsive forces between molecules that increase rapidly at very small intermolecular distances.

• 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.
  • In the case of the latter, the force is comparatively weak.
  • Circa 1870, the positive end of an electrostatic generator is placed near an uncharged brass cylinder, causing the cylinder to polarize as its left end becomes positive and its right end becomes negative.

• Electric Fields and Conductors

  • It measures units of force exerted per unit of charge, and its SI units are N/C.
  • A charged conductor at electrostatic equilibrium will contain charges only on its outer surface and will have no net electric field within itself.
  • Provided a conductor is at electrostatic equilibrium, the electric field upon the surface will be aligned perpendicularly with respect to that surface.
  • But as the surface becomes more sharply curved, charge can be found more densely packed in areas, even if the conductor is at electrostatic equilibrium.
  • Repulsive forces towards the more sharply curved surface on the right aim more outward than along the surface of the conductor.