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Physics · MOTION IN A PLANE
हिन्दीThe magnitude of a three-dimensional position vector \( \mathbf{r} = 3\hat{i} + 4\hat{j} + 12\hat{k} \) is:
Correct answer · Option 4
\( 13 \)
Explanation
\( |\mathbf{r}| = \sqrt{x^2 + y^2 + z^2} = \sqrt{3^2 + 4^2 + 12^2} = \sqrt{9 + 16 + 144} = \sqrt{169} = 13 \).
