Physics - Error Question with Solution | TestHub

A rod$\mathrm{P}$of length$1 \mathrm{m}$, is hinged at one end$\mathrm{A}$and there is a ring attached to the other end. Another long rod$\mathrm{Q}$is hinged at$\mathrm{B}$and it passes through the ring. The rod$\mathrm{P}$is rotated about an axis which is perpendicular to the plane in which both rods are present and the variations between the angles$\mathrm{\theta }$and$\varphi$are plotted as shown.The distance between the hinges$\mathrm{A}$and$\mathrm{B}$is