RRB NTPC previous year question paper

 previous year question paper / PDF

RRB NTPC previous year question paper

Answer blow

1. The efficiency of an incandescent lamp is—
(A) 30 lumens/watt
(B) 12 lumens/watt
(C) 20 lumens/watt
(D) 40 lumens/watt

2. The sodium vapor lamp gives full brilliancy—
 (A) Immediately
(B) After 3 to 5 minutes
(C) After 10 to 15 minutes
(D) After 30 minutes

3. The efficiency of sodium vapor lamp is—
(A) 100 lumens/watt
(B) 80 lumens/watt
(C) 40 lumens/watt
(D) 20 lumens/watt

4. After interruption of supply, the sodium discharge lamp will start—
(A) Immediately
(B) After 3 to 5 minutes
(C) After 10 to 15 minutes
(D) After 15 to 20 minutes

5. The average life of sodium vapor lamp is—
(A) 3000 hours
(B) 4000 hours
(C) 5000 hours
(D) 10,000 hours

6. Sodium vapor lamp can be operated in—
(A) Any position
(B) A horizontal position
(C) Vertical position
(D) An inclined position

7. Mercury vapor lamp can be operated in—
(A) Any position
(B) Horizontal position
(C) Vertical position
(D) An inclined position

8. The average life of mercury vapor lamp is—
(A) 500 hours
(B) 1000 hours
(C) 2000 hours
(D) 3000 hours

9. Choke is used in series with the sodium vapor lamp for—
(A) Reducing the voltage
(B) Stepping up the voltage
(C) stabilize the discharge
(D) Improving the power factor

10. The sodium vapor lamp installed in street lighting in our country operate on—
(A) 440 V, 3φ supply
(B) 400 V, 1φ supply
(C) 230 V, 1φ supply
(D) 110 V, 1φ supply

 11. Efficiency of gas filled lamp as compared to vacuum lamp is—
(A) Same
(B) Double
 (C) Three times
(D) Four times

12. A good illumination will be, when the light is—
(A) More
 (B) Dim
 (C) Uniform and adequate
(D) Diffused

13. The illumination level required for a living room is—
(A) 200 lux
(B) 50 to 60 lux
(C) 6 to 10 lux
(D) 100 lux

14. The uniform distribution of light depends upon—
(A) Space height ratio
(B) Type of the lamps used
(C) Type of reflectors used
(D) Mounting height of the source

15. The illumination in a room depends upon—
(A) color of the walls
(B) color of the ceiling
(C) color of walls and ceiling both
(D) Type of reflector used

ANSWER

1. (B) 2. (C) 3. (C) 4. (B) 5. (A) 6. (B) 7. (C) 8. (D) 9. (C) 10. (C) 11. (B) 12. (C) 13. (B) 14. (A) 15. (C)