Electric Potential Calculator
Calculate electric potential from a point charge using V = kQ/r. Free online physics calculator with instant results, interactive charts, and breakdowns.
About This Calculator
The Electric Potential Calculator computes the electrostatic potential at any point in space due to a single point charge using the fundamental formula V = k·q / r, where k is Coulomb's constant (≈ 8.99 × 10⁹ N·m²/C²), q is the charge in coulombs, and r is the distance from the charge in meters. This tool is essential for physics students, electrical engineers, and anyone studying electromagnetism who needs to quickly compute electric potential values.
The calculator uses the precise value of Coulomb's constant derived from the vacuum permittivity: k = 1/(4πε₀). Results are displayed in volts (V), the SI unit of electric potential. The interactive breakdown shows each step of the calculation, including the charge, distance, and constant values used. The chart visualizations help users understand how charge and distance contribute to the resulting electric potential.
About Electric Potential
Electric potential at a point is defined as the amount of work done in moving a positive test charge from infinity to that point against the electrostatic force. It is a scalar quantity measured in volts (V). A key concept in electromagnetism, electric potential helps us understand how charges interact in electric fields without dealing with vector forces directly.
The electric potential due to a positive charge is positive, while that due to a negative charge is negative. The potential decreases with distance from the charge — following an inverse relationship (V ∝ 1/r). This calculator handles charges in scientific notation (e.g., 1e-6 for 1 microcoulomb) and distances in any metric unit.
Frequently Asked Questions
How do I calculate electric potential of a point charge?
Multiply the charge q by Coulomb's constant (k ≈ 8.99 × 10⁹ N·m²/C²), then divide by the distance r from the charge. The formula is V = k·q / r.
Can electric potential be negative?
Yes, electric potential can be negative. The electrostatic potential at a point due to a positive charge is positive. If the charge is negative, the electric potential is also negative.
What is electric potential difference?
The electric potential difference between two points A and B is defined as the work done to move a positive unit charge from A to B. The SI unit of potential difference is the volt (V).
Is electric potential a scalar or a vector quantity?
Electric potential is a scalar quantity as it has no direction. Unlike the electric field which is a vector, electric potential has magnitude only.
What is the SI unit of electric potential?
The SI unit of electric potential is the volt (V), which equals one joule per coulomb (J/C). One volt means one joule of work is done per coulomb of charge.
What is the electric potential of a charge at an infinite distance?
Zero. The electric potential at a point due to a charge is inversely proportional to the distance between them. As distance approaches infinity, the electric potential approaches zero.
How is electric potential different from electric field?
Electric potential (V) is a scalar quantity representing potential energy per unit charge, while electric field (E) is a vector quantity representing force per unit charge. They are related by E = -∇V.