JEE Mains · Physics · STD 12 - Electric charges and fields
- JEE Mains 2025
- Easy
- MCQ
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : Net dipole moment of a polar linear isotropic dielectric substance is not zero even in the absence of an external electric field.
Reason (R) : In absence of an external electric field, the different permanent dipoles of a polar dielectric substance are oriented in random directions.
In the light of the above statements, choose the most appropriate answer from the options given below :
Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) (A) is not correct but \((\mathrm{R})\) is correct
Step-by-step Solution
Detailed explanation
A : Since polar dielectrics are randomly oriental \(\overrightarrow{\mathrm{P}}_{\mathrm{net}}=\overrightarrow{0}\).
R : If \(\overrightarrow{\mathrm{E}}\) is absent, polar dielectric remain polar & are randomly oriented.
R : If \(\overrightarrow{\mathrm{E}}\) is absent, polar dielectric remain polar & are randomly oriented.
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