3.7 Electric Forces and Free-Body Diagrams

Electric Forces and Free-Body Diagrams

Electrostatic Force & Coulomb's Law

• Electrostatic force is a fundamental force that arises between electrically charged particles. It is one of the four fundamental forces in the universe, along with the strong nuclear force, the weak nuclear force, and the gravitational force.
• Coulomb's law states that the electrostatic force between two charged particles is directly proportional to the product of the charges of the particles and inversely proportional to the square of the distance between them. This can be written as F = kq1q2/r^2, where F is the force between the particles, k is a constant known as Coulomb's constant, q1 and q2 are the charges of the particles, and r is the distance between the particles.
• Coulomb's law is a fundamental principle that is used to describe the electrostatic force between charged particles in many different physical situations, including the behavior of electrons in atoms, the movement of charged particles in electric circuits, and the forces between charged particles in electrostatic discharge.
• Electrostatic force can be either attractive or repulsive, depending on the charges of the particles. If the charges are the same, the force is repulsive, while if the charges are different, the force is attractive.
• Electrostatic force is an important concept in many fields of science and engineering, including physics, chemistry, and electrical engineering. Understanding the principles of electrostatic force is essential for understanding many aspects of the natural world and for designing and building a wide range of technological devices.

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Free Body Diagrams (FBD)

The image shows arrows pointing as the Electric forces.

1. Identify the object of interest. This is the object that you will be drawing the free-body diagram for. It is important to clearly define the boundaries of the object, as this will help you to identify all of the forces acting on it.
2. Determine the direction of the forces. In a problem involving electric forces, you will need to consider both the magnitude and the direction of the forces acting on the object. The direction of the forces should be represented as arrows pointing in the direction that the force is acting.
3. Identify the electric forces acting on the object. In a problem involving electric forces, there will likely be multiple forces acting on the object. These forces may include the electric force between charged particles, the force of friction, and any other external forces such as gravity or the force of a spring.
4. Draw the free-body diagram. Using the information you have gathered, draw a diagram showing the object of interest and the direction and magnitude of all of the forces acting on it. Make sure to label each force and include a scale for the magnitude of the forces.
5. Solve the problem. Once you have drawn the free-body diagram, you can use it to solve the problem by applying the principles of Newton's laws or other relevant physical principles. This may involve calculating the acceleration of the object, the net force acting on it, or other quantities of interest.