Question

An incompressible liquid flows through a horizontal tube as shown in the following fig. Then the velocity v of the fluid is

• A. 3.0 m/s
• B. 1.5 m/s
• C. 1.0 m/s
• D. 2.25 m/s

Answer 1

Answer: (C)

1.0 m/s

Answer 2

If the liquid is incompressible then mass of liquid entering

through left end, should be equal to mass of liquid coming out

from the right end.

$\therefore\mspace{6mu} M = m_{1} + m_{2}$

⇒ $Av_{1} = Av_{2} + 1.5A.v$

⇒ $A \times 3 = A \times 1.5 + 1.5A.v$

⇒ $v = 1\mspace{6mu} m/s$