11. What can one say about the electric potential everywhere on a conductor? Explain why the static electric field inside a conductor is zero. Does this still hold if the

conductor has a hollow cavity within it? Why or why not? Why is the concept of electric potential crucial for determining electric fields when conductors are present? What is meant by capacitance? How is capacitance defined?What are its units? Describe in detail what is meant by a "parallel-plate capacitor." Show how to calculate the capacitance of a parallel-plate capacitor? What does it mean to “charge a capacitor?"