CBSE Class 12 · 2024 · CapacitanceMultiple Choice

Which of the following statements about dielectrics is correct?

(A)A polar dielectric has no net dipole moment in the absence of an external field.
(B)The net dipole moment of the induced dipoles is along the direction of the applied electric field.✓ Correct
(C)Dielectrics contain free charges.
(D)The field produced by the induced surface charges inside a dielectric is along the external field.

Answer: (B)

Solution

When a dielectric is placed in an external field, the induced (or aligned) dipoles point along the applied field, so the net induced dipole moment is along

E

— option (B). Dielectrics have no free charges, and the field of the induced surface charges opposes (not aids) the external field, so the other options are wrong.

CBSE Class 12 Board · 2024 · Single correct option

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