The square of the resultant of two equal forces acting at a point is equal to three times their product. Angle between them is

Step-by-step solution

Let F₁ and F₂ be the two forces acting at a point, then their resultant, array ll & F_ R = F₁²+F₂²+2 F₁ F₂ Given, & F₁=F₂=F & F_ R = 2 F²+2 F² & F_ R ²=2 F²(1+ )...(i) As per question, & F_ R ²=3 F₁ F₂=3 F² & 2 F²(1+ )=3 F² [ using Eq. (i)] 1+ = 3 2 & = 1 2 or =60^ array