Question

Find the magnitude of resultant force.

• A. $\sqrt{2}F$
• B. $\sqrt{3}F$
• C. $\sqrt{7}F$
• D. 10 $F$

Answer 1

The correct option is C $\sqrt{7}F$

Magnitude of resultant force,
$R=\sqrt{A^2+B^2+2AB\cos \theta }$
$=\sqrt{F^2+(2F{)}^2+2\times F\times 2F\times \cos {60}^{\circ }}$
$=\sqrt{F^2+4F^2+2F^2}$
$R=\sqrt{7}F$