Coulomb Law - Electrical Engineering Gate

# Electrical Engineering Gate

Online Electrical Engineering Study Site

## Tuesday, October 14, 2014

Coulomb's Law is one of the basic ideas of electricity in physics. The law looks at the forces created between two charged objects. As distance increases, the forces and electric fields decrease. This simple idea was converted into a relatively simple formula. The force between the objects can be positive or negative depending on whether the objects are attracted to each other or repelled

The Formula
Coulomb's law describes the force between two charged particles

Here, F is the force between the particles, qa and qb are the charges of particles and b. The separation between the particles is r, and k is a constant, 8.99x10(Nm2/C2). Note that the force falls off quadratically, similarly to the behavior of the gravitational force. The force is attractive, when F is negative, hence when the charges have opposite sign. Opposites attract - like charges repel. Of course, remember that force is a vector, which in this case points parallel to r