The magnetic field lines never intersect each other because if two or more lines intersect each other than it means that at that point of intersection, the magnetic field has two directions at the same point. This is not possible for a magnetic field to point in more than one direction at the same point.
Q. What are the similarities and differences between gravitational and electric fields?
Electric vs Gravitational Force
Table of Contents
- Q. What are the similarities and differences between gravitational and electric fields?
- Q. Can electric fields be negative?
- Q. Why do field lines not intersect each other?
- Q. Can two equipotential surfaces intersect?
- Q. Why do the electrostatic field lines not form Closed Loop?
- Q. Why must an electric field line leave the surface of a conductor at right angles?
- Q. Why the interior of a conductor can have no excess charge in the static situation?
- Q. What is the electric field at the surface of a conductor?
| Similarities | Differences |
|---|---|
| Both have fields | Electric force can be both repulsive and attractive but gravity only attracts |
| Both have potential lines | Electric force results from charge but gravitational force results from mass |
Q. Can electric fields be negative?
An electric field can never be negative. An electric field is a force experienced by the charge divided by the magnitude of the charge.
Q. Why do field lines not intersect each other?
Electric lines of force never intersect because, at the point of intersection, two tangents can be drawn to the two lines of force. This means two directions of the electric field at the point of intersection, which is not possible.
Q. Can two equipotential surfaces intersect?
No, it is not possible for two equipotential surfaces to intersect. This is because if two equipotential surfaces intersect, then there will be two values of potential at the point of intersection, which is not possible.
Q. Why do the electrostatic field lines not form Closed Loop?
Electric lines of force due to two positive charges start from either charge and end at infinity. In all cases we see that electric lines of force , either from infinity or from a positive charge never come back to the same point , and hence they don’t form closed loops.
Q. Why must an electric field line leave the surface of a conductor at right angles?
this is because there is no potential gradient along any direction parallel to the surface , and so no electric field parallel to the surface. This means that the electric lines of force are always at right angle to the equipotential surface.
Q. Why the interior of a conductor can have no excess charge in the static situation?
When forces of internal elec. field and external electric field are equal, they cancel each other since they are in opposite directions. Thus a static charge distribution occurs and there is NO EXCESS CHARGE inside a conductor.
Q. What is the electric field at the surface of a conductor?
The electric field is zero inside a conductor. Just outside a conductor, the electric field lines are perpendicular to its surface, ending or beginning on charges on the surface. Any excess charge resides entirely on the surface or surfaces of a conductor.
