Conventionally, the field strength around a charged object is the direction of the force acting on a .

Any charged body has the capacity to effect any test charge that comes inside its field or region. It can be also defined as,

"The total amount or magnitude of force,F or intensity felt by any unit test charge when it enters an electromagnetic or electric field."

Explanation:

A unit test charge inside an electric field:

When a unit test charge enters a given parameters or area set by the charged particle then it will surely experience a force,F equal to the magnitude of that charge body and it will be different as it continues to move closer or far inside the field.

waves moving from a fast medium to a slow medium will experience a reflection as light travels more slowly than red light. total internal reflection occurs when the critical angle is.