Power Plant Engineering Objective Questions

41. Which of the following are not repayable after a stipulated period ?

(a) Fixed deposits.
(b) Shares.
(c) Bonds.
(d) Cash certificates.

42. During summer season load on the system increases, this is due to

(a) increase in demand of water supply.
(b) increased business activity.
(c) increased use of fans, air coolers and air conditioners.
(d) vacations in schools and institutions.

43. The connected load of a domestic consumer (medium income group ) is usually about

(a) 2 – 5 kW
(b) 10 – 20 kW
(c) 20 – 30 kW
(c) below 1 Kw

44. Power demand can be estimated approximately by

(a) load survey method.
(b) mathematical method.
(c) statistical method.
(d) economic parameters.
(e) all of the above.

45. A load curve is a plot of

(a) load versus duration of time.
(b) load versus current.
(c) load versus time.
(d) total number of units generated versus time.

46. The chronological load curve indicates

(a) variation in demand factor during 24 hours.
(b) variation in demand from instant to instant during 24 hours.
(c) the total energy consumed up to different times of the day.
(d) the total number of hours for which a particular load lasts during the day.

47. The area under the load curve represents

(a) system voltage.
(b) current.
(c) energy consumed.
(d) maximum demand.
(e) average demand.

48. The area under daily load curve divided by 24 gives

(a) average load for the day.
(b) maximum demand.
(c) connected load.
(d) demand factor.

49. Which of the following statements regarding load curve is true ?

(a) The area under the curve gives average demand.
(b) The ratio of area under the load curve to the total area of the rectangle in which it is contained gives the load factor for the day.
(c) The area of the load curve divided by the number of hours gives the load factor.
(d) The area of the load curve divided by the number of hours gives the demand factor.

50. Load curve of a power generating station is of always

(a) negative slope.
(b) zero slope.
(c) positive slope.
(d) any combination of (a), (b) and (c).

51. Load curve helps in deciding the

(a) total installed capacity of the plant.
(b) size of the generating units.
(c) operating schedule of the generating units.
(d) all of the above.

52. Load duration curve gives

(a) the variations of load during different hours of the day.
(b) average load.
(c) the number of hours for which a particular load lasts during the day.
(d) none of the above.

53. The load duration curve for unity load factor will be of

(a) rectangular shape.
(b) triangular shape.
(c) L – shape.
(d) I – shape.

54. The mass curve represents

(a) average load.
(b) the total energy consumed by the load up to a particular time in a day.
(c) the number of hours for which a particular load lasts during the day.
(d) the variation of load during different hours of the day.

55. A mass curve can be plotted from

(a) load duration curve.
(b) chronological load curve.
(c) energy load curve.
(d) both load duration curve and chronological load curve.

56. Integrated load duration curve representing total number of units (kWh) generated for a given demand in kW can be plotted directly from

(a) load curve.
(b) load duration curve.
(c) mass curve.
(d) any of these.

57. In a load duration curve for an integrated power system, the uppermost crest represents the energy contributed by which one of the following?

(a) Base power stations.
(b) Major thermal stations.
(c) Peaking hydro or gas turbine stations.
(d) Non-conventional power stations.

58. During which season the load on a power system is maximum ?

(a) Autumn.
(b) Rainy.
(c) Summer.
(d) Winter.

59. Maximum demand on the power system is

(a) the greatest of all ‘short time interval averaged’ demand during a period.
(b) instantaneous maximum value of kW supplied during a period.
(c) instantaneous maximum value of kVA supplied during a period.
(d) maximum value of units (kWh) supplied during a period.

60. The power system experiences peak demand from

(a) midnight to 8 A.M.
(b) 8 A.M. to 2 P.M.
(c) 2 P.M. to 6 P.M.
(d) 6 P.M. to 10 P.M.