Question

Maximum torque acting on an electric dipole of moment 3 x 10-29 Cm in a uniform electric field E is 6 x 10-25 Nm. Find E.​

Answer 1

Answer:

• Maximum torque (τ) = 6 × 10⁻²⁵ Nm
• Dipole moment (P) = 3 × 10⁻²⁹ Cm
• Electric field (E) = ?
• θ = angle between P and E

Calculation :

$\implies \sf\tau_{(maximum)} = PE \sin(\theta)$

• Torque is maximum at an angle 90°.

$\implies \sf6 \times {10}^{ - 25} = 3 \times {10}^{ - 29} \times E \times \sin( {90}^{ \circ} )$

$\implies \sf6 \times {10}^{ - 25} = 3 \times {10}^{ - 29} \times E \times 1$

$\implies \sf E = \dfrac{6 \times {10}^{ - 25} }{3 \times {10}^{ - 29} }$

$\implies \sf E = \dfrac{6 \times {10}^{ - 25} \times {10}^{29} }{3 }$

$\implies \underline{ \boxed{ \red{ \bf E = 2 \times {10}^{4} \: N/C }}}$