A moving coil galvanometer has a coil with 175 turns and area 1 cm2. It uses a torsion band of torsion constant 10-6 N-m/rad. The coil is placed in a magnetic field B parallel to its plane. The coil deflects by 1° for a current of 1 mA. The value of B (in Tesla) is approximately :

Question

A moving coil galvanometer has a coil with 175 turns and area 1 cm2. It uses a torsion band of torsion constant 10-6 N-m/rad. The coil is placed in a magnetic field B parallel to its plane. The coil deflects by 1° for a current of 1 mA. The value of B (in Tesla) is approximately : (A) 10-3 (B) 10-1 (C) 10-4 (D) 10-2

Tardigrade Admin · Accepted Answer

τ = vecM × vecB C θ =i NAB 10-6 ×(π/180) = 10-3 ×10-4 ×175 × B B =10-3 Tesla.

$1 0^{- 3}$

$1 0^{- 1}$

$1 0^{- 4}$

$1 0^{- 2}$

$τ = M \times B$
$Cθ = i N A B$
$1 0^{- 6} \times \frac{π}{180} = 1 0^{- 3} \times 1 0^{- 4} \times 175 \times B$
$B = 1 0^{- 3}$ Tesla.

Q. A moving coil galvanometer has a coil with 175 turns and area 1cm2. It uses a torsion band of torsion constant 10−6N−m/rad. The coil is placed in a magnetic field B parallel to its plane. The coil deflects by 1∘ for a current of 1mA. The value of B (in Tesla) is approximately :

10−3

10−1

10−4

10−2

τ=M×B Cθ=iNAB 10−6×180π​=10−3×10−4×175×B B=10−3 Tesla.

$1 0^{- 3}$

$1 0^{- 1}$

$1 0^{- 4}$

$1 0^{- 2}$

$τ = M \times B$
$Cθ = i N A B$
$1 0^{- 6} \times \frac{π}{180} = 1 0^{- 3} \times 1 0^{- 4} \times 175 \times B$
$B = 1 0^{- 3}$ Tesla.