Changes

Using Gauss' law one can derive the following relationships for the electric field of a uniform spherical charge distribution:

<math> E_r(r) = \frac{\rho}{3\epsilon_0}r, \ \ \ \ \ \ \ r\le a </math>

A list of all the 2D output data files generated at the end of a simulation can be viewed in [[EM.Cube]]’s Data Manager. To open this dialog, click the <b>Data Manager</b> [[Image:fdtd_datamanagerb.png]] button of Simulate Toolbar, or use the keyboard shortcut <b>Ctrl+D</b>, or access the menu <b>Simulate &rarr; Data Manager</b>, or right click on the Data Manager item in the “Observables” section of the Navigation Tree and select <b>Open Data Manager…</b>

Select the data file “Sensor_1_X_ETotal.DAT” and double-click on it or click the View button of Data Manager to see its contents. You will find a spreadsheet with two columns, one for the X values in the project units and the other for the total electric field along the X-axis in V/m. While “Sensor_1_X_ETotal.DAT” is selected in the Data Manager, click the <b>Plot</b> button to open "EM.Grid". For multiple file selection, use the keyboard’s <b>Ctrl Key</b>, or use the <b>Shift Key</b> to select a range of rows in the list. The total E-field is plotted as functions of the coordinate X on a Cartesian graph in EM.Grid. Note that the field increases linearly from r = 0 to r = 5mm, where it reaches a value of 1.88V/m as we calculated earlier, and it then drops down as 1/r².