Question

A multilayer coil of 2000 turns of fine wire is 20 mm long and has a thickness 5 mm of winding. If the coil carries a current of 5 mA, the mmf generated is (a) 10 A . t (c) 2000 A .t (b) 500 A . t (d) None of the above Answers

Answer 1

Gives

n=2000 turn

$i=5mA$

Magnetomotive force $(F)=ni(A.t)$

Magnetomotive force=turn$\times$ area

$F=2000\times5\times10^{-3}A .t$

$F=10A.t$

Option (a) is correct