A) \[u=\frac{{{u}_{1}}+{{u}_{2}}}{2}\]
B) \[u=\sqrt{{{u}_{1}}{{u}_{2}}}\]
C) \[u=\sqrt{\frac{{{u}_{1}}}{{{u}_{2}}}}\]
D) \[\frac{2}{u}=\frac{1}{{{u}_{1}}}+\frac{1}{{{u}_{2}}}\]
Correct Answer: D
Solution :
Mean velocity,\[v=\frac{Total\,\,displacement}{Total\,\,time}\] \[=\frac{x+x}{\frac{x}{{{v}_{1}}}+\frac{x}{{{v}_{2}}}}=\frac{2{{v}_{1}}{{v}_{2}}}{{{v}_{1}}+{{v}_{2}}}\] \[\Rightarrow \] \[\frac{2}{v}=\frac{1}{{{v}_{1}}}+\frac{1}{{{v}_{2}}}\]You need to login to perform this action.
You will be redirected in
3 sec