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JEE PHYSICS MCQ: MOTION IN PLANE

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Consider the following statements about three vectors a→,b→\overrightarrow{{a}}, \overrightarrow{{b}} and c→\overrightarrow{{c}} that have non-zero magnitudes. It follows b→=c→\overrightarrow{{b}}=\overrightarrow{{c}}

(i) if a→⋅b→=a→⋅c→\overrightarrow{\mathrm{a}} \cdot \overrightarrow{\mathrm{b}}=\overrightarrow{\mathrm{a}} \cdot \overrightarrow{\mathrm{c}}

(ii) if a⃗×b⃗=a⃗×c⃗b⃗\vec{a} \times \vec{b}=\vec{a} \times \vec{c} \quad \vec{b} must be perpendicular to c→\overrightarrow{\mathrm{c}}
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Correct option: C
(i) only
Option B is correct because neither statement (i) nor (ii) necessarily implies that b→=c→\overrightarrow{{b}}=\overrightarrow{{c}} when dealing with dot and cross products of vectors.

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