Question:medium

If $ \vec{a} $ and $ \vec{b} $ are two unit vectors and $ \theta $ is the angle between them, then $ |\vec{a} + \vec{b}| $ is a unit vector if $ \theta $ is:

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If the sum of two unit vectors is also a unit vector, they must be at $120^{\circ}$ to each other.

Updated On: Apr 8, 2026

$\pi/3$
$\pi/2$
$2\pi/3$
$\pi/4$

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The Correct Option is C

Solution and Explanation

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If \( \vec{a} \) and \( \vec{b} \) are two unit vectors and \( \theta \) is the angle between them, then \( |\vec{a} + \vec{b}| \) is a unit vector if \( \theta \) is:

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The Correct Option is C

Solution and Explanation

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