How do electrical field lines indicate the strength of an electric field?

Question

How do electrical field lines indicate the strength of an electric field?

Answer 1

The density of lines tells you the strength.

Answer 2

The greater the density of lines, the number of lines in a specific area or volume, the greater the strength of the electric field.

Ex. 100 E-field lines in  a square meter has a greater electric field strength than 10 E-field lines in a square meter.

The E-field density is described by D= episilon * E, where E is the E-field strength or intensity.

Hope that helps.