Each of the three insulators forming a string has a self capacitance of C farad. The shunt capacitance of each insulator is 0-2 C to earth and 0-1 C to line. A guard-ring increases the capacitance of line of the metal work of the lowest insulator to 0-3 C. Calculate the string efficiency of the arrangement: (i) with the guard ring, (ii) without guard ring. [(i) 95% (ii) 86-13%

4. Use this information to answer Question 4-6: Below is the capacitance-voltage curve measured for a Schottky contact made on n-type GaAs at T = 300 K. In this plot, the capacitance has the unit of F/cm² and voltage is in unit of V. 1/C² x 1015 3.0 → Va -2.0 0.9 What is the built-in potential, oi, in unit of V? Answers within 5% error will be considered correct. Enter answer here 5. Calculate doping densiy in GaAs, Np, in unit of cm 3. Answers within 5% error will be considered correct. Enter answer here

All electronic components are formed from p type and n type materials. What factors determine what kind of components will be formed?

Silicon is doped with a boron concentration of 4×1018/cm3. Is boron a donor or acceptor impurity? Find the electron and hole concentrations at 300 K. Is this material n-type or p-type? Find the electron and hole mobilities. What is the resistivity of the material?