What should be the maximum average velocity of water in a tube of diameter 0.5 cm , so that the flow is laminar? The viscosity of water is `0.00125 Nsm^(-2)`.

Explanation

To determine the maximum average velocity of water in a tube of diameter 0.5 cm for laminar flow, we can use the concept of Reynolds number. The flow is considered laminar when the Reynolds number (Re) is less than 2000.

### Step-by-Step Solution:

1. **Convert the diameter from cm to meters**:
\[ D = 0.5 \text{ cm} = 0.5 \times 10^{-2} \text{ m} = 0.005 \text{ m} \]
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