The minimum length of pipe electrode used for earthing should not be less than
Right Answer is:
The pipe used as an earth electrode is galvanized and perforated. Its diameter is 38.1 mm and its length is 2 m. The length may be increased to 2.75 m in the case of dry soil.
Another pipe of 19.05 mm diameter and of length 2.45 m is connected at the top of the above-mentioned pipe.