[[Image:fdtd_lec1_wavelength.png|center]]
[[Image:fdtd_lec1_9_nevigationtree.png|350x|right]] For your resonant dipole to be half-wave, it can be approximated at 150mm.
{{Note|If you have a mouse with a scroll wheel, you can use the scroll wheel to zoom in or zoom out while you draw the line. You can also rotate the view using the right mouse button, or pan the view using the right mouse button while holding the keyboard’s Shift Key down.}}
[[Image:fdtd_lec1_9_nevigationtree.png|350x|right]] Once your drawing is complete, you can zoom to fit your stucture into the screen using the keyboard shortcut <b>Ctrl+E</b> or by clicking the Zoom Extents [[Image:fdtd_zoomextents.png]] button of View Toolbar. After you have rotated or panned the view, you can always restore EM.Cube’s standard perspective view using the keyboard’s <b>Home Key</b> or by clicking the <b>Perspective View</b> [[Image:fdtd_perspective.png]] button of View Toolbar.
In EM.Cube’s [[FDTD Module]], objects are grouped together and organized by material under the “Physical Structure” node of the Naviation Tree. Since you selected no material for your line object, the first drawn object is automatically assigned a <i>PEC_1</i> material group. The default perfect electric conductor (PEC) group is set as the active material. When a material group is set as active, its name appears in bold letters, and all subsequently drawn objects will be placed under that material node. Any material group can be set as the active material by right-clicking on its name in the Navigation Tree and selecting <b>Activate</b> from the contextual menu.
==Computational Domain & Boundary Conditions==