Q. A body is under the action of two mutually perpendicular forces of 3 N and 4 N. The resultant force acting on the body is
A) 7 N
B) 1 N
C) 5 N
D) Zero
Explanation
(c) Resultant force,
$F = \sqrt{F_{1}^{2} + F_{2}^{2} + {2F}_{1}F_{2}\cos\theta}$
$= \sqrt{(3)^{2} + (4)^{2} + 2 \times 3 \times 4\cos{90{^\circ}}}$
$= 5$ N
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.