Question

If two forces of equal magnitude f each, act at a point such that their resultant is also of magnitude f, what is the angle between the two forces

Answer 1

f^2=f^2+f^2+2f^2cosX

f^2=2f^2(1+cosX)

f^2=2f^2×2cosX/2

f=2fcosX/2

1/2=cosX/2

X/2=60

X=30