Question

( F_{1} rightarrow 0, overrightarrow{F_{2}} )
leswltant forey ( =sqrt{F_{1}^{2}+F_{2}^{2}+2 f_{1} f_{2} cos theta} )
and IResultont forkel ( =2 mathrm{E} mathrm{I} ). ( begin{aligned} f_{1}=& 2 f_{2} 2 F_{2} &=sqrt{4 f_{2}^{2}+F_{2}^{2}+4 F_{2}^{2} cos theta} 4 F_{2}^{2} &=5+2^{2}+4+2^{2} cos theta cos theta &=-frac{1}{4} theta &=cos ^{-1}(-1 / 4) end{aligned} )

# Q.11 Two forces, F, and F, are acting on a body. One force is double that of the other force and the resultant is equal to the greater force. Then the angle between the two forces is - (A) cos' (1/2) (B) cos(-1/2) (C) cos(-1/4) (D) cos (1/4)

Solution