Electric Field Visualization
Field Parameters
Charge Properties
Display Options
Visualization Options
Quick Presets
Electric Field Formulas
Instructions
- Click anywhere on the canvas to add a charge
- Drag existing charges to move them
- Double-click on a charge to remove it
- Use the slider to adjust the magnitude of new charges
- Field lines start from positive charges and end on negative charges
What are Electric Field Lines?
Electric field lines are a visual representation of the electric field around charged objects. They show the direction a positive test charge would move if placed in the field. The density of field lines indicates the strength of the electric field - closer lines mean a stronger field. Field lines always start on positive charges and end on negative charges (or extend to infinity).
Coulomb's Law and Electric Field
The electric field E created by a point charge Q at a distance r is given by E = kQ/r², where k is Coulomb's constant (k ≈ 8.99 × 10⁹ N⋅m²/C²). The field points radially outward from positive charges and radially inward toward negative charges. For multiple charges, the total electric field at any point is the vector sum of the individual fields (superposition principle).
Properties of Electric Field Lines
Electric field lines have several important properties: (1) They never cross each other. (2) The tangent to a field line at any point gives the direction of the electric field at that point. (3) The density of field lines is proportional to the magnitude of the electric field. (4) Field lines begin on positive charges and end on negative charges. (5) The number of lines leaving or entering a charge is proportional to the magnitude of that charge.
Equipotential Lines
Equipotential lines (shown as dashed curves) are lines of constant electric potential. No work is required to move a charge along an equipotential line. Equipotential lines are always perpendicular to electric field lines. For a point charge, equipotential lines are concentric circles. In systems with multiple charges, they form more complex shapes but maintain the property of being everywhere perpendicular to the electric field.
Electric Dipole
An electric dipole consists of two equal and opposite charges separated by a distance. The electric field pattern of a dipole is characteristic - field lines emerge from the positive charge and curve around to terminate on the negative charge. Dipoles are important in many areas of physics and chemistry, from molecular bonds to antenna design. The dipole moment p = Qd, where Q is the charge magnitude and d is the separation vector.
Applications
Understanding electric fields and field lines has numerous applications: designing capacitors and electronic components, studying molecular structure and chemical bonding, particle accelerators and mass spectrometers, electrostatic precipitation and pollution control, medical imaging techniques like EEG and EKG, lightning protection systems, and fundamental research in plasma physics and fusion energy.