A 24 V DC source feeds two equal 120 ohm resistors in series. What voltage appears from their junction to the negative rail?

12 V, because equal series resistors divide the source equally under Kirchhoff's voltage law

A lagging AC load draws 8 kW real power and 10 kVA apparent power. What is its power factor, and what does the figure mean?

0.8 lagging; current lags voltage

Three equal loads are star-connected to a balanced three-phase supply. How are line and phase quantities related?

Line voltage is root-three times phase voltage, while line current equals phase current

A coil has 30 ohm resistance and 40 ohm inductive reactance at the supply frequency. What is the impedance magnitude, and how does current phase compare with voltage?

50 ohm; current lags voltage because net reactance is inductive

Exam resources

Railway LDCE Assistant Signal & Telecom Engineer

Limited Departmental Competitive Examination through which serving Group C railway staff of the signal and telecommunication department are promoted to Assistant Signal & Telecom Engineer in Group B against the 30% quota. Covers railway signalling, interlocking, block working and telecommunication, with general knowledge, official language and establishment and financial rules.

Practice tests

Quizzes

10 questions · ~10 minutes · instant rank & AI diagnosis

Double-checked questions Real exam pattern 1 free test every month, then ₹19 per test

Try before you buy free, no payment

SampleRailway LDCE Assistant Signal & Telecom Engineer · Free sample (4 questions)A few questions in the exact player you get after buying: the clock, the question palette, then your score and every answer explained.

Railway LDCE Assistant Signal & Telecom Engineer — DC and AC Circuit Fundamentals

Start here

10 Qs · ~10 min