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3.1 vectors — Physics STD 11 Science — Question

Rajasthan BoardEnglish MediumSTD 11 SciencePhysics3.1 vectors1 Mark
MCQ
Two vectors $\overrightarrow A $ and $\overrightarrow B $ are at right angles to each other, when
  • A
    $\overrightarrow A + \overrightarrow B = 0$
  • B
    $\overrightarrow A - \overrightarrow B = 0$
  • C
    $\overrightarrow A \times \overrightarrow B = 0$
  • ✓
    $\overrightarrow A \,.\,\overrightarrow B = 0$
✓

Answer

Correct option: D.
$\overrightarrow A \,.\,\overrightarrow B = 0$
d
(d) $\vec A.\vec B = \,|\vec A|.|\vec B|.\cos \theta = \vec A.\vec B.\cos 90^\circ = 0$

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