Physics - Vectors Question with Solution | TestHub

(B) Given, $P+Q=R$ After reversing direction of $R$, we gel $\begin{array}{l}r=-P-Q\\ S=-P-Q\end{array}$ So let angle between $P$ and $Q$ be $Q$ So resurtants. $\begin{array}{l}{R}^2=p^2+Q^2+2PQ\cos \theta ...(1)\\ s^2=p^2+Q^2-2PQ\cos \theta ...(2)\end{array}$ Adthing equation (1) and (2) $R^2+S^2=2\left(P^2+Q^2\right)$ So, the corvect answer is $R^2+s^2=2\left(p^2+Q^2\right)$