A solid metal sphere of radius a = 1.30 cm is surrounded by a concentric spherical metal shell of inner radius b = 1.80 cm and outer radius c = 2.30 cm. The inner sphere has net charge $Q_1 = 4.50 \mu C$, and the outer spherical shell has net charge $Q_2 = -7.90 \mu C$.
(For reference see class notes)
What is the radial component of the electric field $E_r$ at a point located at radius r = 1.50 cm, i.e., between the two conductors? ($E_r$ is positive if $\vec{E}$ points outward, negative if $\vec{E}$ points inward.)
What is $E_r$ at a point located at radius r = 2.70 cm, i.e., outside the outer shell?
Use Gauss' Law, with a Gaussian surface surrounding both spheres. What is the total charge inside your Gaussian surface? (Don't forget to convert centimeters to meters.)
