Utilization of Electrical Energy Mid - I, September - 2014

1.The main drawback of electric drive is that ______________
  • It is cumbersome drive
  • It’s initial cost is more
  • Its maintenance cost is more
  • Electric power supply failure makes the drive standstill
Answer: D
2.Which of the following motor is preferred for traction works ______
  • Universal motor
  • DC series motor
  • Synchronous motor
  • 3-pahse Induction motor
Answer: B
3.In which of the following motor, speed control by injecting e. m. f. in the rotor circuit is possible.
  • DC shunt motor
  • DC series motor
  • Synchronous motor
  • Slip ring Induction motor
Answer: D
4.Which of the following heating methods has maximum power factor?
  • Arc heating
  • Dielectric heating
  • Induction heating
  • Resistance heating
Answer: D
5.In the indirect Resistance heating method, maximum heat transfer takes place by _____
  • Radiation
  • Convection
  • Induction
  • Conduction
Answer: C
6.Hysteresis loss and eddy current loss are used in ____________
  • Dielectric heating
  • Induction heating of steel
  • Heating of brass
  • Resistance heating
Answer: B
7.For arc welding, DC is produced by which of the following ______
  • Motor generator set
  • Regulator
  • Transformer
  • Induction motor
Answer: A
8.Resistance welding cannot be used for _________
  • Ferrous materials
  • Dielectric
  • Non-ferrous metals
  • Motor frames
Answer: B
9.Light waves travel with a velocity of
  • 3 x 1010cm/s
  • 3 x 1012cm/s
  • 3 x 1015 cm/s
  • 3 x 1018 cm/s.
Answer: A
10.Solid angle ‘ ’ is given by _________________
Answer: B
11.Hoists and cranes require ___________________ starting torque.
Answer: High
12.The process of smoothing out the fluctuating load (such as in rolling mills) is known as _________
Answer: Load equalization
13.In direct heating ________________ frequency voltage is used.
Answer: High
14.Direct core type induction furnace suffers from _________________ effect.
Answer: Pinching
15.The transformer used in a welding set is _______________ transformer.
Answer: Step down
16.The disadvantage of resistance welding is ______________
Answer: High initial and maintenance cost
17.Electric arc welding process produces temperature upto _________________
Answer: 55500 C
18.A 250V lamp has a total flux of 1500 lumens and takes a current of 0.4A, Lumens per watt is ________________
Answer: 15
19.The illumination is directly proportional to the cosine of the angle made by the normal to the illuminated surface with the direction of the incident flux. This statement is associated with _________________ law.
Answer: Lambert's cosine law
20.Polar curves are used to determine __________________
Answer: MHCP, MSCP