Calculate the velocity with which water emerges from an orifice in a tank if the gauge pressure is `2 xx 10^5` N/m before the flow starts.

Explanation

To calculate the velocity with which water emerges from an orifice in a tank given a gauge pressure of \(2 \times 10^5 \, \text{N/m}^2\), we can use the principles of fluid mechanics, specifically Torricelli's theorem.

### Step-by-Step Solution:

1. **Understand the relationship between pressure and height**:
The gauge pressure \(P\) can be related to the height \(h\) of the water column using the formula:
\[
P = \rho g h
...