Use Task Manager. Another way of opening File Explorer is to use the Task Manager. You'll have to open Task Manager, switch to More details, select the File menu and then click or tap on Run new task. Inside the Create new task window, write explorer and press Enter or OK.
Sources of electric field. Causes and description. Electric fields are caused by electric charges or varying magnetic fields. The former effect is described by Gauss's law, the latter by Faraday's law of induction, which together are enough to define the behavior of the electric field as a function of charge repartition and magnetic field.
The magnitude of the field is proportional to the number of field-lines per unit area passing through a small surface normal to the lines. Thus, field-lines determine the magnitude, as well as the direction, of the electric field. In particular, the field is strong at points where the field-lines are closely spaced, and weak at points where they are far apart. The electric field-lines associated with a positive point charge are a set of unbroken, evenly spaced (in solid angle) straight-lines which radiate from the charge--see Fig. 9.