### Solved Question Paper for Lecturer in Electronics & Communications Engineering in DTTE, GNCTD conducted by UPSC

11. A resistance R is connected in series with a parallel combination of two resistances 12 Ω and 8 Ω. If the power dissipated in the circuit is 70 𝑊 when the applied voltage is 20 𝑉 across the circuit. The resistance 𝑅 will be nearly:

(a) 1.07 Ω

(b) 0.91 Ω

(c) 0.83 Ω

(d) 0.75 Ω

12. A 120 𝑉 ac circuit contains 10 Ω resistance and 30 Ω reactance in series. The average power in the circuit will be nearly:

(a) 134 𝑊

(b) 144 𝑊

(c) 158 𝑊

(d) 168 𝑊

13. A 25 ℎ𝑝, 250 𝑉 dc series motor has armature resistance of 0.1 Ω, field resistance of 0.05 Ω and brush contact drop 3 𝑉. When the line current is 80 𝐴, the speed is 600 rpm and when the line current is 100 𝐴, the speed will be nearly:

(a) 394 rpm

(b) 474 rpm

(c) 556 rpm

(d) 636 rpm

14. A 200/400-𝑉, 10-𝑘VA , 50 Hz single-phase transformer has at full-load a copper loss of 120 𝑊 . If it has an efficiency of 98 % at full-load unity power factor, the efficiency of the transformer at half load 0.8 power factor lagging will be:

(a) 82 %

(b) 87 %

(c) 92 %

(d) 97 %

15. A 3- phase, 6- pole 50 Hz induction motor delivers 3.73 kW at 950 rpm . If the stator loss is 250 𝑊 , the stator input will be:

(a) 4420 𝑊

(b) 4340 𝑊

(c) 4260 𝑊

(d) 4180 𝑊

16. In a 25 𝑘VA, 3300/230 𝑉, 1-phase transformer, the iron and full-load copper losses are respectively 350 𝑊 and 400 𝑊 . The efficiency at half load 0.8 power factor will be nearly:

(a) 83 %

(b) 88 %

(c) 94 %

(d) 99 %

17. A 3-phase induction motor is wound for 4-poles and is supplied from a 50 Hz system. When speed of the rotor is 600 rpm, the rotor frequency will be:

(a) 30 Hz

(b) 35 Hz

(c) 40 Hz

(d) 45 Hz

18. If a 6-pole induction motor running from a 50 Hz supply has an emf in the rotor of frequency 2.5 Hz. The speed of motor will be:

(a) 910 rpm

(b) 930 rpm

(c) 950 rpm

(d) 970 rpm

19. Which of the following are the engineering materials?

1. Metals and alloys

2. Ceramics and glasses

3. Organic polymers

(a) 1 and 2 only

(b) 1 and 3 only

(c) 2 and 3 only

(d) 1, 2 and 3

20. The volume of a Face-Centered Cubic (FCC) unit cell in terms of the atomic radius R will be:

Share:

## Featured Post

### UPSC Civil Service Preliminary Paper-1 Previous Year Solved Question Papers

Civil Service Preliminary Paper-1 Previous Year Solved Questions for the year 2019 Civil Service Preliminary Paper-1 Previous Year Solved Qu...

Name

Email *

Message *