The square represents a cross section of a cube. Use the test charge to explore the direction of the electric field inside the cube. Click the cursor anywhere inside the cube to measure the magnitude of the electric field. Use it also to determine the dimensions of the cube. Find the flux through each side of the cube.

Situation one
Top: X [0 ] Left: X [-8]
Right: X [8] Bottom: X [0 ]
Situation two
Top: X [0 ] Left: X [8]
Right: X [8] Bottom: X [0]
 

Credits

Physlet problem authored by Scott Bonham.