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 440 cubic metres in 5 minutes. The inner radius of the pipe should be :	Answers.
A) √2 m	B) 2 m	C) 1⁄2 m	D) 1⁄√2 m	E) None of these
Let inner radius of the pipe be r.   Then, 440 = 22⁄7 × r2 × 7 × 5   or r2=440/22×5=4   or r = √4 = 2 m   Answer 2 m
<result>B</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 440 cubic metres in 5 minutes. The inner radius of the pipe should be :