JEE Mains · Physics · STD 12 - 1. Electric charges and fields
An electric dipole has a fixed dipole moment \(\vec P\) which makes angle \(\theta \) with respect to \(x-\)axis. When subjected to an electric field \(\overrightarrow {{E_1}} \) \(=E\)\(\hat i\) it experiences a torque \(\overrightarrow {{T_1}} \) =\(\;\tau \hat k\) When subjected to another electric field \(\overrightarrow {{E_2}} = \sqrt 3 {E_1}\hat j\) it experiences torque \(\overrightarrow {{T_2}} \) = \( - \overrightarrow {{T_1}} \) The angle \(\theta \;\) is.......\(^o\)
- A \(30\)
- B \(45\)
- C \(60\)
- D \(90\)
Answer & Solution
Correct Answer
(C) \(60\)
Step-by-step Solution
Detailed explanation
\(\mathrm{T}=\mathrm{PE} \sin \theta\) Torque experienced by the dipole in an electric field, \(\quad \vec{T}=\vec{P} \times \vec{E}\) \(\vec{p}=p \cos \theta \hat{i}+p \sin \theta \hat{j}\) \(\vec{E}_{1}=\overrightarrow{E i}\)…
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