Creeping is avoided by __________ A. reversing the polarity of

creeping-is-avoided-by-a-reversing-the-polarity-of

Creeping is avoided by __________

A. reversing the polarity of the voltage

B. drilling two diametrically opposite holes

C. holding the disc

D. increasing the friction

I have been asked this question by my school principal while I was bunking the class.

Enquiry is from Errors in Single Phase Energy Meters in division Measurement of Power and Related Parameters of Electrical Measurements

Right answer is B. drilling two diametrically opposite holes

Easiest explanation: In an energy meter, creeping causes the disc to rotate even when there is no current flowing. By drilling two diametrically opposite holes under the edge of the poles of a shunt magnet, rotation of the disc is limited to a minimum value.