A slab of copper of thickness b is thrust into aparallel-plate capacitor of plate area A and plate separation d; the slab is exactly halfway between the plates. (a) What is the capacitance after the slabis introduced? (b) If a potential difference V ismaintained between the plates, what is the ratio of the storedenergy before to that after the slab is inserted?(c) How much work is done on the slab as it isinserted? (d) Is the slab sucked in or must it bepushed in?
Copper is a kind of metal. What is its dielectric constant?