Chapter 5, Problem 5.60P

Suppose that a coin is tossed three so that the sample space is Let X represent the number of heads that can come up. i) Find the probability function corresponding to the random variable X. Assuming that the coin is fair ii) Find the distribution function for the random variable X. iii) Obtain its graph.

Q9 A single-phase transformer, 2500 / 250 V, 50 kVA, 50 Hz has the following parameters, the Primary and secondary resistances are 0.8 ohm and 0.012 ohm respectively, the primary and secondary reactance are 4 ohm and 0.04 ohm respectively and the transformer gives 96% maximum efficiency at 75% full-load. The magnetizing component of-load current is 1.2 A on 2500 V side. 1- Draw the equivalent circuit referred to primary (H.V side) and inserts all the values in it 2- Find out Ammeter, voltmeter and wattmeter readings on open-circuit and short-circuit test. If supply is given to 2500 V side in both cases. Ans. O.C. Test (Vo= 2500 V, lo=1.24 A, Wo=781.25 w) S.C. Test (Vsc =164.924 V, Isc =20 A, Wsc =800 w )

Q2-A)- Enumerate the various losses in transformer. Explain how each loss varies with (Load current, supply voltage). B)- Draw the pharos diagram at load on primary side.