If the angle between two vectors $A$ and $B$ is $120^{\circ}$, its resultant $C$ will be
The angle between the two vectors $\vec A = 3\hat i + 4\hat j + 5\hat k$ and $\vec B = 3\hat i + 4\hat j + 5\hat k$ is ....... $^o$
The vector sum of two forces is perpendicular to their vector differences. In that case, the force