Concept #1: Gauss' Law
Practice: Rank the flux through surfaces A, B and C in the figure below from greatest to smallest.
Practice: The flux through the four surfaces of a pyramid are given below
Φ1 = 10 Nm2 /C Φ3 = 8 Nm2 /C
Φ2 = 20 Nm2 /C Φ4 = −15 Nm2 /C
What is the charge enclosed by the pyramid?
Example #1: Electric Field due to Hollow Shell
Example #2: Surface Charge Density
Practice: A spherical, conducting shell has a charge of –6C. If a 4C charge were placed at the center of the shell, what is the electric field at 4 cm? At 12 cm?