It is required to fix a pipe such that water flowing through it at a speed of 7 metres per minute fills a tank of capacity 1760 cubic metres in 10 minutes. The inner radius of the pipe should be : Pick one.
A) √2 m	B) 2 m	C) 1⁄2 m	D) 2√2 m	E) None of these
Let inner radius of the pipe be r.   Then, 1760 = 22⁄7 × r2 × 7 × 10   or r2=1760/22×10=8   or r = 2√2 m   Answer 2√2 m
<result>D</result>
It is required to fix a pipe such that water flowing through it at a speed of 7 metres per minute fills a tank of capacity 1760 cubic metres in 10 minutes. The inner radius of the pipe should be :