Question

What is the formula for the length of mean turn of magnet coils?

(a) length of mean turns = 3.14 * (inside diameter of coil + depth of windings)

(b) length of mean turns = 3.14 / (inside diameter of coil + depth of windings)

(c) length of mean turns = 3.14 * (inside diameter of coil * depth of windings)

(d) length of mean turns = 3.14 + (inside diameter of coil + depth of windings)

This question was addressed to me by my school principal while I was bunking the class.

The query is from Design of Magnet Coils in section Design of Electromagnets of Design of Electrical Machines

Answer 1

Correct option is (a) length of mean turns = 3.14 * (inside diameter of coil + depth of windings)

To explain: The inside diameter of the coil is first calculated. Next, the depth of windings is next calculated and on substitution gives the length of mean turns.