A proposed hydroelectric station has an available head of 30 m, a catchment area of 50 x 106 sq. m, the rainfall for which is 120 cm per annum. If 70% of the total rainfall can be collected, calculate the power that could be generated. Assume the following efficiencies: Penstock 95%, Turbine 80%, and Generator 85%.

a. 253 kW

b. 678 kW

c. 214 kW

d. 925 kW

1. 3.A 3-phase ,Y- connected synchronous motor operates at 480 volt,50 Hz,2-pole,0.8 pf leading.The armature winding resistance is j1.5 ohm.The efficiency of the motor is 95%.The output torque of the motor at rated conditions is 350 Nm .Calculate: (a)the output power (b)the input power and the input current (c)the internal generated voltage Ea (d)the converted power (e)power losses (20 points)

Single phase transformer 10kVA, 2200/220v, 50Hz has the following
configure:
R1=4Ω, X1=5Ω, Rfe=25kω, XM=4kω, R2=0.04 Ω, X1=0.05 Ω
The transformer operates at rated voltage and feeds rated load
with a power factor of 0.8 inductive. To be identified:
1. The voltage fluctuation and the degree of efficiency.
2. The excitation current of the transformer.
3. The energy it consumes in a 24-hour period (in kWh) if it works under a load of 16
hours a day and the rest he works without load.