Question

When a body moves with velocity v1 for first half time of the journey and v2 for remaining half time of the journey.If v1 and v2 are(15+_0.5)m/s and (25+-0.7)m/s respectively,then average velocity within error limits is

Answer 1

Average velocity, $$\begin{gathered} v_{av}=\frac{v_{1}t+v_{2}t}{2t}=\frac{v_1+v_2}{2}=\frac{\left(15\pm 0.5\right)+\left(25\pm 0.7\right)}{2}=\frac{\left(40\pm 1.2\right)}{2} \\ \Rightarrow v_{av}=\left(20\pm 0.6\right)m/s \end{gathered}$$