3. A 10 kVA, single-phase transformer has a turns ratio of 15:1 and is supplied from a 2,0 kV supply. Neglecting losses, determine : - the full load secondary current, - The minimum value of load resistance which can be connected across the secondary winding without the kVA rating being exceeded, and the primary current.

The load current in a system is 100 A. the short-circuit current for the smallest fault is     100 A. An overcurrent capable of carrying a current of 5 A continuously is to be used. (a) Suggest a suitable C.T. ratio                  (b) What will be the current for the smallest fault?            (c) Will the protective C.T be able to faithfully reproduce the fault current?

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1. A Zone 2 fault is detected in 25 cycles of a 60 Hz power system and the circuit breaker clears in 5 cycles. Calculate the fault clearing time for this case. a) 60 ms b) 500 ms c) 120 ms d) 150 ms 2. The Burden on a CT should always be kept a) High b) Low c) Either, because burden does not affect the CT d) At the rated burden value for the CT 3. The purpose of backup protection is a) To increase speed b) To leave no blind spots c) To guard against failure of primary d) To increase reach 4. In distance protection scheme, which Zone is set to trip instantaneous without any delay? a) Zone 3 b) Zone 2 c) Zone 1 d) All of the above 5. The protective relay is provided to: 1) Provide additional safety by limiting arcing current during circuit breaker operation. 2) Close the contacts when the actuating quantity attains a certain predetermined value. a) Only 1 b) Only 2 c) Both 1 and 2 d) None of these

can you do question iii please?

36) which type of circuit is used during repetitive actions such as when the heart beats? a) reverberating circuit  b) divergent circuit  c) convergent circuit  d) all of these can be used during repetitive activities