See the attached file for questioins

A VarleyBridge is connected to a faulty three-core copper cable by two identical copper leads of resistance R_l.

(a) Show that for the initial reading (connection to earth);

                        2R_x = 2R_c – R_i

 (b)      By multiplying the rhs brackets and collecting terms, show the effect of the leads is given by:

 (c) Determine the distance to the fault by modifying the expression in (b) and using  

(d) Using  

(e) Determine the distance to a fault on a 200 m, 120 mm² copper cable

if copper 10 mm² test leads of length 10 m are used and .