Engineering VIVA

This one is for those who had nightmares during their Engineering Viva's . They 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 AC 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!"

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)

Examiner: "What is a step-up transformer?"

Student: "A transformer that is put on top of electric poles."

Examiner (smiling): "And then what is a step-down transformer?"
Student (hesitantly):"Uh - A transformer that is put in the x-udment or in a pit?"

Examiner (pouncing): "Then what do you call a transformer that is installed on the ground?" (Student knows he is caught-can't answer)
Examiner (impatiently): "Well?"
Student (triumphantly): "A stepless transformer, sir!"