Torques τ 1 and τ2 are required for magnetic needle to remain perpendicular to the magnetic fields B1 and B2 at two different places. The ratio B1/B2 is

Question

Torques τ 1 and τ2 are required for magnetic needle to remain perpendicular to the magnetic fields B1 and B2 at two different places. The ratio B1/B2 is (A)  (τ 2/τ 1)  (B)  (τ 1/τ2)  (C)  (τ 1+τ 2/τ 1-τ 2)  (D)  (τ 1-τ 2/τ 1+τ 2)

Tardigrade Admin · Accepted Answer

Torque, τ =M B sin θ τ1 =M B1 sin 90°=M B1 τ2 =M B2 sin 90°=M B2 or (M B1/M B2) =(τ1/τ2) ∴ (B1/B2) =(τ1/τ2)

Q. Torques $τ_{1}$ and $τ_{2}$ are required for magnetic needle to remain perpendicular to the magnetic fields $B_{1}$ and $B_{2}$ at two different places. The ratio $B_{1} / B_{2}$ is

$\frac{τ _{2}}{τ _{1}}$

$\frac{τ _{1}}{τ _{2}}$

$\frac{τ _{1} + τ _{2}}{τ _{1} - τ _{2}}$

$\frac{τ _{1} - τ _{2}}{τ _{1} + τ _{2}}$

$T or q u e, τ = MB sin θ$
$τ_{1} = M B_{1} sin 9 0^{\circ} = M B_{1}$
$τ_{2} = M B_{2} sin 9 0^{\circ} = M B_{2}$
or $\frac{M B _{1}}{M B _{2}} = \frac{τ _{1}}{τ _{2}}$
$∴ \frac{B _{1}}{B _{2}} = \frac{τ _{1}}{τ _{2}}$

Q. Torques τ1​ and τ2​ are required for magnetic needle to remain perpendicular to the magnetic fields B1​ and B2​ at two different places. The ratio B1​/B2​ is

τ1​τ2​​

τ2​τ1​​

τ1​−τ2​τ1​+τ2​​

τ1​+τ2​τ1​−τ2​​