A spherical, non-conducting shell of inner radius = 10.0 cm…

A spherical, non-conducting shell of inner radius = 10.0 cm and outer radius = 15.0 cm carries a total charge Q =  15.0 μC distributed uniformly throughout the volume of the shell. What is the magnitude of the electric field at a distance r =  12.0 cm from the center of the shell?

Light of intensity I0 and polarized horizontally passes thro…

Light of intensity I0 and polarized horizontally passes through three polarizers. The first and third polarizing axes are horizontal, but the second one is oriented 40.0° to the horizontal. In terms of I0, what is the intensity of the light that passes through the set of polarizers?