Best answer by B.E students during viva

It bring back fond memories for those who care to smile at the past:-

Interviewer: Why is a thicker conductor necessary to carry a current in A.C.as compared to D.C. ?
Candidate : An AC current goes up and down (drawing a sinusoid) and requires more space inside the wire, so the wire has to be thicker

External (to student) : "Why does a capacitor block DC but allow AC To pass through
Student: See, a capacitor is like this --- --- , OK. DC comes straight, like this ----------, and the capacitor stops it. But AC,goes UP, DOWN, UP DOWN and jumps right over the capacitor!" ------------------- good one : - )

Interviewer: How will you tell if that wall outlet carries AC or DC?
Candidate: I will put my finger in. If it is pushed away, it is AC. If it gets stuck, it was DC.

Interviewer: H! ow will you reverse direction of an Induction motor?
Candidate: I will remove the four bolts at the x-ud, turn the motor around, and put back the bolts.

Interviewer: How do you start a synchronous motor?
Candidate: Vrrrrrrrmmmmmmmmmmmmmmmmmmm (in rising pitch)
Interviewer: Stop! Stop!
Candidate: rrrrrrrmmmmmmmmmmmmmmmmmmmm (in falling pitch)