Water flows through a horizontal pipe of varying cross-section at the rate of 20 litres per minuts , determine the velocity of water at a point where diameter is `4 cm`

Explanation

To determine the velocity of water at a point where the diameter of the pipe is 4 cm, we can follow these steps:

### Step 1: Convert the flow rate from liters per minute to cubic meters per second.
The flow rate is given as 20 liters per minute. We need to convert this to cubic meters per second.

\[ \text{Flow rate} = 20 \, \text{liters/minute} = \frac{20}{1000} \, \text{m}^3/\text{minute} = \frac{20}{1000 \times 60} \, \text{m}^3/\text{second} = \frac{1}{3} \times 10^{-3} \, \text{m}^3/\text{s} \]
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