Related InterviewSolutions

• A transformer has an efficiency of 60% and works at 5kW. If the secondary voltage is 150 V, then what is the secondary current?(a) 10 A(b) 20 A(c) 30 A(d) 40 AI have been asked this question in an international level competition.This intriguing question comes from Alternating Current in section Alternating Current of Physics – Class 12
• A capacitor, resistor of 10 Ω, and an inductor of 70 mH are in series with an ac source marked 120 V, 70 Hz. If it is found that voltage is in phase with the current, then find out the impedance of the circuit.(a) 5 Ω(b) 10 Ω(c) 100 Ω(d) 900 ΩThis question was addressed to me in an interview.My doubt stems from AC Voltage Applied to a Series LCR Circuit in chapter Alternating Current of Physics – Class 12
• What is the power factor for a series LCR circuit at resonance?(a) Infinity(b) -1(c) 0(d) 1I got this question in an interview for job.My question comes from Power in AC Circuit : The Power Factor topic in section Alternating Current of Physics – Class 12
• Which of the following is usually taken to make the core of a transformer?(a) Aluminum(b) Copper(c) Soft iron(d) Hard ironThis question was posed to me during an interview.I need to ask this question from Alternating Current topic in chapter Alternating Current of Physics – Class 12
• Current remains unchanged in a transformer.(a) True(b) FalseThe question was posed to me during an interview.The above asked question is from Alternating Current topic in chapter Alternating Current of Physics – Class 12
• Identify the expression for average power.(a) Pav=\(\frac {V_o I_o}{2}\)sinΦ(b) Pav=\(\frac {V_o I_o}{2}\)cosΦ(c) Pav=\(\frac {V_o I_o}{4}\)cos⁡Φ(d) Pav=2VoIosin⁡ΦI had been asked this question in an international level competition.Origin of the question is Power in AC Circuit : The Power Factor in section Alternating Current of Physics – Class 12
• Which among the following varies in both magnitude and sign over a cycle?(a) Apparent power(b) Effective power(c) Instantaneous power(d) Average powerThe question was asked in quiz.My doubt is from Power in AC Circuit : The Power Factor in portion Alternating Current of Physics – Class 12
• What is the capacitive reactance of a 5 μF capacitor when it is a part of a circuit whose frequency is 50 Hz?(a) 636.6 Ω(b) 1636.6 Ω(c) 2636.6 Ω(d) 4636.6 ΩThe question was posed to me in an online interview.Origin of the question is AC Voltage Applied to a Capacitor topic in division Alternating Current of Physics – Class 12
• When are the voltage and current in LCR-series ac circuit in phase?(a) XL = XC(b) XL > XC(c) XL < XC(d) IndeterminantThe question was posed to me in homework.This interesting question is from AC Voltage Applied to a Series LCR Circuit in chapter Alternating Current of Physics – Class 12
• Which value of the current do you measure with an a.c. ammeter?(a) Instantaneous current(b) Root mean square value(c) Electromotive force(d) Peak currentThe question was asked by my college director while I was bunking the class.My question comes from AC Voltage Applied to a Resistor in section Alternating Current of Physics – Class 12