Conservation of Electric Energy

Conservation of electric energy refers to the principle that the total electric energy in a closed system remains constant over time. This means that the electric energy can be converted from one form to another, but the total amount of energy remains constant.

Here are some key points about the conservation of electric energy:

• Conservation of electric energy is a fundamental principle in physics and is a consequence of the law of conservation of energy, which states that the total energy of a closed system remains constant.
• In an electric circuit, conservation of electric energy means that the electrical energy supplied to the circuit by the power source is equal to the sum of the energy used by the circuit and the energy stored in the circuit.
• Conservation of electric energy can be used to understand and analyze the operation of electric circuits and devices, including batteries, generators, and transformers.
• Conservation of electric energy is an important concept in electromagnetism and is used in a variety of applications, including electricity generation and distribution, and the design of electronic devices.

Electric Fields & Work

Work in electric fields refers to the work done by the electric field in moving a charged particle from one point to another.

Here are some key points about work in electric fields:

• The work done by the electric field in moving a charged particle from one point to another is equal to the change in electric potential energy of the particle. Electric potential energy is the potential energy of a charged particle in an electric field and is determined by the electric potential at the two points.
• The work done by the electric field can be calculated using the formula W = qΔV, where W is the work done, q is the charge of the particle, and ΔV is the change in electric potential between the two points.
• The work done by the electric field is positive if the electric potential at the final point is higher than at the initial point and negative if the electric potential at the final point is lower than at the initial point.
• Work in electric fields is an important concept in electromagnetism and is used to understand and analyze the operation of electric circuits and devices, including batteries, generators, and transformers.
• The work done by the electric field can be used to calculate the energy stored in an electric field, such as the energy stored in a capacitor.

In order to bring two like charges near each other or to separate two opposite charges, work must be done. Recall from your mechanics courses that W=Fd, where W is the work done on or by the system, F is the net force, and d is the displacement over which the force is applied. Using this in the context of Coulomb's Law, we get

where ΔUE​ is the change in Electric Potential Energy. Like all energies, it is a scalar quantity. If you have a collection of charges, the total UE​ is the sum of all the individual UE​.

Electric Potential Energy can also be expressed in terms of the Electric Field Strength

** Review Note: Conservation of Energy applies here too!**

Electric potential energy is the potential energy of a charged particle in an electric field. It is determined by the electric potential at the position of the charged particle.

Here are some key points about electric potential energy:

• Electric potential energy is represented by the symbol "U" and is measured in units of joules (J).
• Electric potential energy is a scalar quantity, meaning it has only magnitude and no direction.
• Electric potential energy is related to the electric potential at the position of the charged particle. The electric potential is a measure of the electric potential energy per unit charge, and the electric potential energy is the product of the electric potential and the charge of the particle.
• Electric potential energy is an important concept in electromagnetism and is used to understand and analyze the electric forces and electric potential energy in systems containing charged particles.
• Electric potential energy can be converted into other forms of energy, such as kinetic energy (the energy of motion), when a charged particle is moved within an electric field. The total energy of a closed system, including the electric potential energy, is conserved.