Question

Two forces of magnitudes $3N$ and $4N$ act together on an object making an angle ${60}^o$ with each other. Find the resultant force acting on the object.

Answer 1

We know that the resultant force $\left(F\right)=\sqrt{F_1^2+F_2^2+2F_1{F}_2\cos \theta }$

$\Rightarrow F$$=\sqrt{(3{)}^2+(4{)}^2+2\left(5\right)\left(3\right)\cos {60}^0}$

$\Rightarrow F=\sqrt{40N}$

$=2\sqrt{10}N$