Transformation ratio in a single phase transformer is given by .. a. E, /E2 b. N, /N2 c. E, /E, С. d. V, N2

Determine the voltage through the 10 kilo-ohm resistor at terminals a-b. a. 0.21645 b. 6.9264 c. 1.2324 d. 2.3810 e. None of the above

(b) Figure Q4 shows a three-line network. The load currents and the fault levels at various locations are indicated in the figure. The operation time of both the CBs is 0.4 s. The IDMT relay characteristic in terms of PSM is shown in Table Q4. Assume the pickup current of relay is set to 1.5 A, the TMS for Relay 1 is 0.1 and the ratio of current transformer as below CT ratio for relay R₁ = A₁= 100/1; CT ratio for relay R₂ = A₂=200/1 Determine, (i) the TMS value for Relay 2 if fault of 3000A detected at Bus C, and (ii) the actual operating time of Relay 2 if fault of 4800A found at Bus B. Bus A PSM T (sec) Over current Relay 2 Bus B Transmission line: I₁= 200A] Max: IF = 4800 A CB 0.7 S fuse Over current Relay 1 Figure Q4 Table Q4 20 18 16 2.2 2.6 2.8 (Relay operating time = Tx TMS) 14 3.0 Transmission line: I₁= 100A Transmission line: IL = 100A| 12 3.2 10 3.5 Bus Bus Max: IF = 3000 A

Question 4: Choose the correct answer. 1- (Have you decided/ Did you decide) about your holiday yet?. 2- Why are you making a list? B Because (ll go/I'm going) shopping. 3- What (are you doing/do you do) Saturday night? I'm not sure yet. I may go to my friend. (10 marks) 4- Are you enjoying your job more now? No, I'm not. (I'm going to/I will) look for another one. 5- Your team's rubbish! It's 2-0 to United! Come on. It's only half-time. I think they (are going to/could still) win.