Motion in a Plane - Result Question 8

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10. If the angle between the vectors $\vec{A}$ and $\vec{B}$ is $\theta$, the value of the product $(\vec{B} \times \vec{A}) \cdot \vec{A}$ is equal to

======= ####10. If the angle between the vectors $\vec{A}$ and $\vec{B}$ is $\theta$, the value of the product $(\vec{B} \times \vec{A}) \cdot \vec{A}$ is equal to

3e0f7ab6f6a50373c3f2dbda6ca2533482a77bed:content/english/neet-pyq-chapterwise/physics/motion-in-a-plane/motion-in-a-plane—result-question-8.md (a) $B A^{2} \sin \theta$

(b) $B A^{2} \cos \theta$

(c) $B A^{2} \sin \theta \cos \theta$

(d) zero

[2005]

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Answer:

Correct Answer: 10. (d)

Solution:

(d) $(\vec{B} \times \vec{A}) \cdot \vec{A}=\vec{C} \cdot \vec{A}=C A \cos 90^{\circ}=0$.

Dot product of any two perpendicular vector is zero.