Related InterviewSolutions

• A PMMDC motor has an armature resistance of 4.2 ohms. When 6 V supply is applied to motor it runs at 1215 rpm drawing 14.5 mA on no-load. The rotational losses is?(a) 86.1 mW(b) 86.1 W(c) 8.6 W(d) 8.6 mWI had been asked this question in examination.Asked question is from Permanent Magnet DC (PMDC) Motors topic in division DC Motors of Electrical Machines
• PMMDC can only be armature controlled.(a) True(b) FalseI have been asked this question in an internship interview.This interesting question is from Permanent Magnet DC (PMDC) Motors in division DC Motors of Electrical Machines
• How to manage run-away issue for dc shunt motor in industry?(a) By using PMDCmotor(b) By using constant field motors(c) This can not be avoided(d) None of the mentionedI had been asked this question by my school teacher while I was bunking the class.The question is from Permanent Magnet DC (PMDC) Motors in division DC Motors of Electrical Machines
• Why does DC motor sometimes run too fast when under-loaded?(a) Due to weak field(b) Due to high line voltage(c) Due to brush-shifted to neutral(d) All of the mentionedThe question was posed to me in a job interview.This intriguing question originated from Speed Control of DC Motors topic in portion DC Motors of Electrical Machines
• PMDC had no ________ excited machine.(a) electrically(b) magnetically(c) none of the mentioned(d) leastI have been asked this question during an online interview.This interesting question is from Permanent Magnet DC (PMDC) Motors in portion DC Motors of Electrical Machines
• PMMDC offers ______ characteristics.(a) shunt(b) series(c) armature(d) cumulativeI had been asked this question in an interview.The question is from Permanent Magnet DC (PMDC) Motors topic in section DC Motors of Electrical Machines
• PMMDC are smaller in size due to __________(a) ansence of field winding(b) presence of smaller field winding(c) present of magnets(d) Any of the mentionedI got this question by my college professor while I was bunking the class.My doubt is from Permanent Magnet DC (PMDC) Motors in chapter DC Motors of Electrical Machines
• Which type of field winding required in PMMDC?(a) series winding(b) shunt winding(c) cumulative winding(d) none of the mentionedThis question was posed to me in class test.The above asked question is from Permanent Magnet DC (PMDC) Motors in portion DC Motors of Electrical Machines
• Run-away for large DC machine is avoided by using _________(a) a turn or two of cumulative compounding(b) compensating winding(c) stablizer winding(d) all of the mentionedI have been asked this question in class test.This is a very interesting question from Speed Control of DC Motors topic in chapter DC Motors of Electrical Machines
• The qualities aspired to obtain a good permanent magnet is/are ____________(a) high residual flux(b) low coercivity(c) high coercivity(d) high residual flux and high coercivityThis question was posed to me in examination.My question comes from Permanent Magnet DC (PMDC) Motors topic in portion DC Motors of Electrical Machines