A : Since polar dielectrics are randomly oriental Pnet=0.
R : If E is absent, polar dielectric remain polar & are randomly oriented.
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…
JEE Main 2025 — Physics Electromagnetism
2025mcqeasy
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 :
Official previous-year question
Held on 2 Apr 2025 · Verified 6 Jul 2026.
Options
- A
(A) is correct but (R) is not correct
- B
Both (A) and (R) are correct but (R) is not the correct explanation of (A)
- C
Both (A) and (R) are correct and (R) is the correct explanation of (A)
- D
(A) is not correct but (R) is correct
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