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Question
Maximum torque acting on an electric dipole of moment 3×10-29 Cm in a uniform electric field E is 6 × 10-25 Nm. Find E.
Solution
\[ \overrightarrow{τ} = \overrightarrow{p} × \overrightarrow{E} \]
∴ \[\overrightarrow{E}\] = `τ/p [∵ θ = 90°] =(6xx10^25 Nm)/(3xx 10^-29 Cm) = 2 xx 10^4 NC^-1`
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