A) \[2m{{l}^{2}}\]
B) \[\sqrt{3}\,m{{l}^{2}}\]
C) \[3\,m{{l}^{2}}\]
D) \[\,m{{l}^{2}}\]
Correct Answer: C
Solution :
The situation is shown in figure. \[{{l}_{BD}}=m\times D{{P}^{2}}+m\times B{{Q}^{2}}+m\times C{{A}^{2}}\] \[=2\times m\times {{\left( \frac{\sqrt{2}l}{2} \right)}^{2}}+m\times {{(\sqrt{2}l)}^{2}}=3m{{l}^{2}}\]You need to login to perform this action.
You will be redirected in
3 sec