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Is the Vector Sum of the Unit Vectors → I and → I a Unit Vector? If No, Can You Multiply this Sum by a Scalar Number to Get a Unit Vector? - Physics

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प्रश्न

Is the vector sum of the unit vectors  \[\vec{i}\] and \[\vec{i}\] a unit vector? If no, can you multiply this sum by a scalar number to get a unit vector?

 

थोडक्यात उत्तर
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उत्तर

No, the vector sum of the unit vectors \[\vec{i}\] and  \[\vec{i}\]  is not a unit vector, because the magnitude of the resultant of \[\vec{i}\] and \[\vec{j}\] is not one.
Magnitude of the resultant vector is given by
R = \[\sqrt{1^2 + 1^2 + \cos90^\circ} = \sqrt{2}\]

Yes, we can multiply this resultant vector by a scalar number \[\frac{1}{\sqrt{2}}\] to get a unit vector.

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पाठ 2: Physics and Mathematics - Short Answers [पृष्ठ २८]

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एचसी वर्मा Concepts of Physics Vol. 1 [English] Class 11 and 12
पाठ 2 Physics and Mathematics
Short Answers | Q 10 | पृष्ठ २८

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