Question

If the angle between two forces increases, the magnitude of their resultant

• A. decreases
• B. increases
• C. remains unchanged
• D. first decreases and then increases

Answer 1

The correct option is A decreases

From the parallelogram law, the resultant of the force is given by
$F_{res}=\sqrt{F_1^2+F_2^2+2F_1{F}_2\cos \theta }$
As $\theta$ increase, $\cos \theta$ decreases. So, magnitude of resultant force decreases.