CBSE-XI-Physics
02: Physics and Mathematics
- #10Is the vector sum of the unit vectors
i→and
j→a unit vector? If no, can you multiply this sum by a scalar number to get a unit vector?Ans : No, the vector sum of the unit vectors `` \stackrel{\to }{i}`` and `` \stackrel{\to }{j}`` is not a unit vector, because the magnitude of the resultant of `` \stackrel{\to }{i}`` and `` \stackrel{\to }{j}`` is not one.
Magnitude of the resultant vector is given by
R = `` \sqrt{{1}^{2}+{1}^{2}+\mathrm{cos}90°}=\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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