Table 1.

Minimum coil size satisfying $\eta <10$ for different air gap width.

Air Gap (mm)	1	2	3	4	5	6	7	8	9
“amin” (mm)	40	39	38	37	36	36	35	35	35
$w$ (mm)	102	101.5	101	100.5	100	102	101.5	103.5	105.5