CBSE Class 12 · 2005 · ElectrostaticsVery Short Answer

An electrostatic field line cannot be discontinuous. Why?

Solution

A field line gives the direction of the force on a positive test charge at every point. The force, and hence the field, has a definite direction and non-zero value at every point in the field region, so the line cannot break. A field line can only start on a positive charge and end on a negative charge (or at infinity); it is continuous in between.

CBSE Class 12 Board · 2005 · Subjective

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