Question

Magnitude of the resultant of two vectors, $A$ and $B$ is given by square root of _____________.

Answer 1

Define the magnitude of the resultant of two vectors.
Let us suppose that there are two vectors namely $A$ and $B$.

The magnitude of the resultant vector $\left(R\right)$ of these $A$ and $B$ vectors can be written as:

$R=\sqrt{A^2+B^2+2AB\cos \theta }$
where $\theta$ is the angle between $A$ and $B$.

Hence, the magnitude of the resultant of two vectors, $A$ and $B$ is given by the square root of $\left(A^2+B^2+2AB\cos \theta \right)$.