Less than 1 m/sec
1 m/sec
1.5 m/sec
2 m/sec
Answer is Wrong!
Answer is Right!
The correct answer is: A. Less than 1 m/sec
The maximum velocity for laminar flow is given by the Hagen-Poiseuille equation:
$$v_max = \frac{8Q}{\pi r^4 \mu}$$
where $Q$ is the volumetric flow rate, $r$ is the radius of the pipe, and $\mu$ is
the dynamic viscosity of the fluid.In this case, we have $Q = 1 \text{ m}^3/\text{s}$, $r = 4 \text{ cm} = 0.04 \text{ m}$, and $\mu = 0.4 \text{ cm}^2/\text{s}$. Substituting these values into the Hagen-Poiseuille equation, we get:
$$v_max = \frac{8
\cdot 1}{\pi \cdot 0.04^4 \cdot 0.4} = 0.072 \text{ m/s} = 7.2 \text{ cm/s}$$Therefore, the maximum velocity for laminar flow is less than 1 m/sec.
The other options are incorrect because they are greater than 1 m/sec.