A body is acted upon by the force and another force

PHYSICS · Single correct · CBSE · Physics · Motion in a Plane · Motion in a Plane

Problem

A body is acted upon by the force

\vec{F}_1=3\mathbf{i}+4\mathbf{j}+\mathbf{k}

and another force

\vec{F}_2=-\mathbf{i}+2\mathbf{j}+5\mathbf{k}

. If

\vec{F}_2

is reversed in direction and doubled in magnitude before being applied together with

\vec{F}_1

, what is the magnitude of the net force on the body? (a)

\sqrt{146}

(b)

\sqrt{76}

(c)

\sqrt{106}

(d)

\sqrt{186}