Question

Water is flowing in a pipe of diameter 4 cm with a velocity 3 m/s. The water then enters into a tube of diameter 2 cm. The velocity of water in the other pipe is

• A. 3 m/s
• B. 6 m/s
• C. 12 m/s
• D. 8 m/s

Answer 1

Answer: (C)

12 m/s

Answer 2

$a _ { 1 } v _ { 1 } = a _ { 2 } v _ { 2 }$ ⇒ $\frac { v _ { 2 } } { v _ { 1 } } = \frac { a _ { 1 } } { a _ { 2 } } = \left( \frac { r _ { 1 } } { r _ { 2 } } \right) ^ { 2 }$

⇒ $v _ { 2 } = 3 \times ( 2 ) ^ { 2 }$= 12 m/s