45. •• An pair of identical and initially neutral thin, square metal slabs, measuring 5.00 cm on a side have a 2.00 mm spacing between them. With the slabs oriented horizontally, together they are placed in a vertical uniform external field of field strength 500 N/C. After a few seconds, it is noted that the top surface of the top slab is positively charged.

(a) What is the direction of the external field, up or down?

(b) What is the sign of the charge on the other three slab surfaces?

(c) What is the direction and strength of the field between the plates?

(d) What is the charge

(magnitude) on each surface of the slabs?