An electric field line is a component of a diagram representing an electric field. It is a line that corresponds with the electric field at every point along its length. The direction of the electric field line shows the direction of the electric field.
- Drawing field lines to show an electric field is a way of visualizing the direction and strength of the field at given points in space.
- Electric field lines point away from their origin at a positively charged object and towards their termination at a negatively charged object.
- At a sub-atomic scale, the electric field around a positively charged particle (such as a proton) is directed away from the charge, and the electric field around a negative charge particle (such as an electron) is directed towards the charge.
- The density of field lines is used to represent the strength of the electric field, with more lines indicating a stronger field.
Drawing field lines
- To draw electric field lines, start by placing a point where you want to visualise the direction of the field between a positively charged and a negatively charged ball bearing.
- The direction of electric field lines between them can be established using a small compass. A compass needle experiences a torque that causes it to align with the electric field.
- By placing a compass needle near an object with a positive or negative, you can trace out the electric field lines by following the direction of the compass needle.
- For example, if you place a compass needle near a positive charge, the compass needle will point towards the charge. This is because positive charges attract electrons, and the electrons in the compass needle will be attracted to the positive charge. If you trace out the direction of the compass needle at different points and connect them you will be tracing out the electric field lines.