SSC JE: Power System Quiz 5 for ESE & GATE EE Exams

Question 1

The following two tariffs are offered to a consumer: Rs. 400 plus Rs. 1.43 per kWh; A flat rate of Rs. 1.83 per kWh. The number of units consumed for which the first tariff will be economical is

Question 2

An industrial consumer has a maximum demand of 150 kW at a load factor of 50%. The tariff is Rs. 900 per kWA of maximum demand per year plus Rs. 1.30 kWh of energy consumed. If the average power factor is 0.75 lagging, the yearly electricity bill is

Question 3

An industrial consumer has a connected load of 50 kW and his maximum demand is 40 kW. On the average, each machine works for 8 hours a day for 300 working days in a year. The tariff is (Rs. 5000 + Rs. 800 per kW of maximum demand + Rs. 1.15 per kWh of energy consumed). The annual bill of the consumer is

Question 4

A supply is offered on the basis of fixed charges of Rs. 30 per annum plus 3 paise per unit or alternative at the rate of 6 paise per unit for the first 400 units per annum and 5 paise per unit for all the additional units. The number of units. The number of units taken per annum for which the cost under the two tariffs become equal is

Question 5

Referring to daily load curve in Fig., the average load is

Question 6

The maximum demand of a consumer is 2 kW and his daily energy consumption is 20 units. His load factor is

Question 7

A synchronous motor having a power consumption of 50 kW is connected in parallel with a load of 200 kW having p.f. of 0.8 lag. The excitation of the motor is adjusted until combined p.f. becomes 0.9 lag. What is the p.f. of synchronous motor?

Question 8

A synchronous motor having a power consumption of 50 kW is connected in parallel with a load of 200 kW having p.f. of 0.8 lag. The excitation of the motor is adjusted until combined p.f. becomes 0.9 lag. What is the leading kVAR supplied by the synchronous motor?

Question 9

It is desired to correct the p.f. to 0.95 by means of static capacitors connected across each phase of a 3-phase, 400 V, 50 Hz motor having a maximum load of 50 kVA at a p.f. of 0.75 lagging. The capacitors are delta connected. The leading kVAR supplied by each capacitor is

Question 10

A workshop is consuming 500 kW at 0.707 p.f. lagging. A synchronous motor is connected to improve the p.f. to 0.95 lagging. The leading reactive power supplied by the synchronous motor is