If $|\,\vec A + \vec B\,|\, = \,|\,\vec A\,| + |\,\vec B\,|$, then angle between $\vec A$ and $\vec B$ will be ....... $^o$
$90$
$120$
$0$
$60$
A body moves due East with velocity $20\, km/hour$ and then due North with velocity $15 \,km/hour$. The resultant velocity..........$km/hour$
$\overrightarrow A \, = \,3\widehat i\, + \,2\widehat j$ , $\overrightarrow B \, = \widehat {\,i} + \widehat j - 2\widehat k$ then find their addition by algebric method.
The vectors $\overrightarrow A $ and $\overrightarrow B$ lie in a plane. Another vector $\overrightarrow C $ lies outside this plane. The resultant $\overrightarrow A + \overrightarrow B + \overrightarrow C$ of these three vectors
If the sum of two unit vectors is a unit vector, then magnitude of difference is