When a current is passed through a suspended moving-coil galvanometer, the deflection of the coil is 9. Then, in the usual notation, the expression is (A) the torsion constant of the helical spring (B) the magnetic dipole moment of the current-carrying coil (C) the current through the coil (D) the torsion constant of the suspension fibre.

When a current is passed through a suspended moving-coil galvanometer,

1.	When a current is passed through a suspended moving-coil galvanometer, the deflection of the coil is 9. Then, in the usual notation, the expression is (A) the torsion constant of the helical spring (B) the magnetic dipole moment of the current-carrying coil (C) the current through the coil (D) the torsion constant of the suspension fibre.
Answer» (D) the torsion constant of the suspension fibre.