
Gravitational Field, Electric Field and Magnetic Field
Comparative study between the Gravitational Field, Electric Field and Magnetic Field
GRAVITATIONAL FIELD |
ELECTRIC FIELD |
MAGNETIC FIELD |
|
Source |
Body mass (punctual or mass distribution) |
Electric charge (punctual or mass distribution) Magnetic field variable in time |
Electric charge in motion – Electric current Electric field variable in time
|
Force |
Proportional to the mass on which it acts
Attraction
![]() bioprofre | Gravitational Field | 01
Open and Incoming |
Proportional to the electrical charge on which it acts
Attraction or Repulsion
![]() bioprofre | Electric Field | 02
Open Incoming: -q Outgoing: +q
|
Proportional to the electrical charge on which it acts
Attraction or Repulsion
![]() bioprofre | Magnetic Field | 03
Close (from N to S) Solenoidal field |
Features |
![]() bioprofre | Gravitational Field, Electric Field and Magnetic Field | 04
![]() bioprofre | Gravitational Field, Electric Field and Magnetic Field | 07 |
![]() bioprofre | Gravitational Field, Electric Field and Magnetic Field | 05
![]() bioprofre | Gravitational Field, Electric Field and Magnetic Field | 08
|
![]() bioprofre | Gravitational Field, Electric Field and Magnetic Field | 06
![]() BioProfe | Gravitational Field, Electric Field and Magnetic Field | 09
|
Conservative Field
In a Conservative Field (Gravitational Field and Electric Field) the equipotential surface is the one which is integrated by all the points where the potential has a same determined value, existing different equipotential surfaces according to the value of the potential.
As it is deduced from Coulomb’s Law, the potential due to a punctual charge is given by the following formula:

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From this formula it is deduced that the equipotential surfaces of the Electric Field created by a punctual charge are concentric spheres with the charge, since all their points are at the same distance, the radius of the charge, and therefore, the same potential:

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As seen in the drawing, the lines of force and the equipotential surfaces are perpendicular to each other. This shows that no work is done when moving a charge within the same equipotential surface:

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And also:

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In each of its points the line of force is tangent to the vector Field Intensity E, and, consequently, also to force F
Non Conservative Field
In a Non-Conservative Field (Magnetic Field) there is no energy associated with the fixed points of the field, as the force of Field of Intensity of Velocity depends with the electric charge q that moves in its sine

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This prevents that a potential function is defined that only depends on the position of the bodies in the Magnetic Field, that is, there is no associated potential energy that is retained when a particle moves within the field.
You can download the App BioProfe READER to practice this theory with self-corrected exercises.