If $$\overrightarrow A \times \overrightarrow B = \overrightarrow B \times \overrightarrow A ,$$ then the angle between $$A$$ and $$B$$ is-
A.
$$\frac{\pi }{2}$$
B.
$$\frac{\pi }{3}$$
C.
$$\pi $$
D.
$$\frac{\pi }{4}$$
Answer :
$$\pi $$
Solution :
$$\eqalign{
& \vec A \times \vec B - \vec B \times \vec A = 0 \cr
& \Rightarrow \vec A \times \vec B + \vec B \times \vec A = 0 \cr
& \therefore \vec A \times \vec B = 0 \cr} $$
Angle between them is $$0,\,\pi ,\,\,{\text{or}}\,\,2\pi $$
from the given options, $$\theta = \pi $$
Releted MCQ Question on Basic Physics >> Kinematics
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