# Voltage, Current and Power in a Star Connected System MCQ’s

This set of Network Theory Multiple Choice Questions & Answers (MCQs) focuses on “Voltage, Current and Power in a Star Connected System”.

1. In three phase system, the line voltage VRY is equal to?
a) phasor sum of VRN and VNY
b) phasor difference of VRN and VNY
c) phasor sum of VRN and VNY
d) algebraic sum of VRN and VNY

2. The relation between the lengths of the phasors VRN and – VYN is?
a) |VRN| > – |VYN|
b) |VRN| < – |VYN|
c) |VRN| = – |VYN|
d) |VRN| >= – |VYN|

3. In star connected system, VRY is equal to?
a) VYR
b) -VYR
c) 2VYR
d) 3VYR

4. In a star connected system, the phasors VRN, VYN are ____ apart.
a) 15⁰
b) 30⁰
c) 45⁰
d) 60⁰

5. In a star connected system, the relation between VYB, Vph is?
a) VYB = Vph
b) VYB = 3√3Vph
c) VYB = 3Vph
d) VYB = √3Vph

6. A symmetrical star connected system has VRN = 230∠0⁰. The phase sequence is RYB. Find VRY.

a) 398.37∠30⁰
b) 398.37∠-30⁰
c) 398.37∠90⁰
d) 398.37∠-90⁰

7. The voltages, VBR ,Vph are related in star connected system is?
a) VBR = 3Vph
b) VBR = 3√3Vph
c) VBR = √3Vph
d) VBR = Vph

8. The relation between VRY, Vph in a star connected system is?
a) VRY = Vph
b) VRY = √3Vph
c) VRY = 3√3Vph
d) VRY = 3Vph

9. A symmetrical star connected system has VRN = 230∠0⁰. The phase sequence is RYB. Find VYB.

a) 398.37∠-30⁰
b) 398.37∠210⁰
c) 398.37∠90⁰
d) 398.37∠-90⁰

10. A symmetrical star connected system has VRN = 230∠0⁰. The phase sequence is RYB. Find VBR.

a) 398.37∠210⁰
b) 398.37∠-210⁰
c) 398.37∠120⁰
d) 398.37∠-120⁰