Question

Bl A co-axial cable can be treated as two straight cylindrical layers with length of h -6 cm, radii of a lcm and b 4 cm, that is filled with air. Let there be a charge ( +12 pC) on the inner layer and - -12 pC) on the outer layer (as shown in Fig. Bla). Assume each layer has negligible thickness. -Q bt Fig. Bla Fig. Blb (1) Find the electric field intensity E (p) and potential difference in the region between the two layers (a< p <b) (in V/m) (Hint: m^dx -I (5 marks) (2) These two concentric cylindrical conducting shells together form a conductor ind the capacitance Ci (in F) (3 marks) (3) If another dielectric layer with permittivity of r2 was inserted between these two layers (the cross section is shown in Fig.B1b), the thickness of dielectric layer d is 1 cm. Find the new capacitance C2 (in F) (4 marks)

Answer 1

opy Gouts la a. aussiaへ Seuface CEI Elachic potanhal VE.dru au dr. 2TGh几 에 ch 2 fh