Question

Rainwater draining from a neighborhood street initially travels at 4 ft/s through a pipe with a cross-sectional area of 15.7 ft2. This pipe connects down the street to another pipe with a cross-sectional area of 65.4 ft2. What would be the speed of the water as it moves through this larger pipe?

Answer 1

Answer:

The  velocity  is $v_2 = 0.96 \ ft/s$

Explanation:

From the question we are told that

   The initial speed is  $v_1 = 4 \ ft/s$

   The  cross -sectional area of the first pipe is  $A_1 = 15.7 \ ft$

   The  cross -sectional area of the second pipe is $A_2 = 65.4 \ ft$

Generally from continuity equation we have that

     $A_1 * v_1 = A_2 * v_2$

So  

     $v_2 = \frac{A_1 * v_1 }{A_2 }$

=>   $v_2 = \frac{15.7 * 4 }{65.4 }$

=>   $v_2 = 0.96 \ ft/s$