A solenoidal induction coil comprising an at least one adjustable coil turn (10 or 11) with a dynamically variable interior cross sectional opening, the at least one adjustable coil turn having a first coil turn end (10b' or 11b') connected to a first adjacent coil turn of the solenoidal induction coil or to a first coil power termination, and a second coil turn end (10b' or 11b') connected to a second adjacent coil turn of the solenoidal induction coil or to a second coil power termination, the at least one adjustable coil turn comprising: a first coil turn segment (10a or 11a) and a second coil turn segment (10b or 11b), the first coil turn segment (10a or 11a) extending from the first coil turn end (10a' or 11a') to a first adjustable coil segment end (10a" or 11a") opposing the first coil turn end (10a' or 11a'), the second coil turn segment (10b or 11b) extending from the second coil turn end (10b' or 11b') to a second adjustable coil segment end (10b" or 11b") opposing the second coil turn end (10b' or 11b'), the first and the second adjustable coil segment ends (10a" and 10b" or 11a" and 11b") movably located next to each other in a closed-segments position to form an electrically continuous connection between the first and the second adjustable coil segment ends (10a" and 10b" or 11a" and 11b"); an adjustable coil turn segment (10c or 11c) electrically connecting the first and second adjustable coil segment ends (10a" and 10b" or 11a" and 11b"); and an adjustable coil segment assembly (10d or 11d) comprising a coil turn segments separator (10d' or 11d') for providing an adjustable coil segment ends distance between the first and the second adjustable coil segment ends (10a" and 10b" or 11a" and 11b"), and an actuator (10d" or 11d") for dynamically adjusting the adjustable coil ends distance characterised in that the interior cross sectional opening of the at least one adjustable coil turn is dynamically variable between the closed-segments position when the adjustable coil segment (10c or 11c) is short-circuited and a variable opened-segments position when the adjustable coil turn segment (10c or 11c) forms an electrically continuous connection between the opposing first and the second adjustable coil segment ends (10a' and 10b' or 11a' and 11b'). a first coil turn segment (10a or 11a) and a second coil turn segment (10b or 11b), the first coil turn segment (10a or 11a) extending from the first coil turn end (10a' or 11a') to a first adjustable coil segment end (10a" or 11a") opposing the first coil turn end (10a' or 11a'), the second coil turn segment (10b or 11b) extending from the second coil turn end (10b' or 11b') to a second adjustable coil segment end (10b" or 11b") opposing the second coil turn end (10b' or 11b'), the first and the second adjustable coil segment ends (10a" and 10b" or 11a" and 11b") movably located next to each other in a closed-segments position to form an electrically continuous connection between the first and the second adjustable coil segment ends (10a" and 10b" or 11a" and 11b"); an adjustable coil turn segment (10c or 11c) electrically connecting the first and second adjustable coil segment ends (10a" and 10b" or 11a" and 11b"); and an adjustable coil segment assembly (10d or 11d) comprising a coil turn segments separator (10d' or 11d') for providing an adjustable coil segment ends distance between the first and the second adjustable coil segment ends (10a" and 10b" or 11a" and 11b"), and an actuator (10d" or 11d") for dynamically adjusting the adjustable coil ends distance characterised in that the interior cross sectional opening of the at least one adjustable coil turn is dynamically variable between the closed-segments position when the adjustable coil segment (10c or 11c) is short-circuited and a variable opened-segments position when the adjustable coil turn segment (10c or 11c) forms an electrically continuous connection between the opposing first and the second adjustable coil segment ends (10a' and 10b' or 11a' and 11b').