If the sum of two unit vectors is also a unit vector. then magnitude of their difference and angle between the two given unit vectors is ..............
$\sqrt{3}, 60^{\circ}$
$\sqrt{3}, 120^{\circ}$
$\sqrt{2}, 60^{\circ}$
$\sqrt{2}, 120^{\circ}$
The vectors $5i + 8j$ and $2i + 7j$ are added. The magnitude of the sum of these vector is
Two forces $F_1 = 3N$ at $0^o$ and $F_2 = 5N$ at $60^o$ act on a body. Then a single force that would balance the two forces must have a magnitude of .......... $N$
Two forces of $10 \,N$ and $6 \,N$ act upon a body. The direction of the forces are unknown. The resultant force on the body may be .........$N$
The magnitude of vector $\overrightarrow A ,\,\overrightarrow B $ and $\overrightarrow C $ are respectively $12, 5$ and $13$ units and $\overrightarrow A + \overrightarrow B = \overrightarrow C $ then the angle between $\overrightarrow A $ and $\overrightarrow B $ is