An air gap is usually inserted in magnetic circuits to

A. E.M.F. B. Current C. Current density D. Conductivity

A. Lowers their power efficiency B. Increases their cost of manufacture C. Leads to their increased weight D. Produces fringing

A. Henry B. Weber C. Ampere-turn/weber D. Ampere/metre

A. Copper loss B. Eddy current loss C. Hysteresis loss D. All of the above