question_answer

    A cylinder of height 20 m is completely filled with water. The velocity of efflux of water (in \[m{{s}^{-1}}\]) through a small hole on the side wall of the cylinder near its bottom, is:

A)  10                                         

B)  20

C)  25.5                                      

D)  5

Correct Answer: B

Solution :

                As,     \[P.E.=K.E.\]                 \[mgh=\frac{1}{2}m{{v}^{2}}\]                 \[v=\sqrt{2gh}\]                 \[=\sqrt{2\times 10\times 20}\]   [Here:\[g=10\,m/{{s}^{2}}\]] \[=20\text{ }m/s\]