Question

At what speed , the velocity head of water is equal to pressure head of 40 cm of mercury .??????????????????????????????????????????

Answer 1

At what speed, the velocity head of water is equal to pressure head of 40 cm of mercury

Solution:

$$h = 40 \text{cm} = 0.4 \text{m} - \text{head mercury column};$$

Velocity head = 40 cm of Hg column $h_w = h \cdot 13.6$ cm of water column.

$$h_w = \frac{v^2}{2g}$$ $$v^2 = 2gh_w$$ $$v = \sqrt{2gh_w} = \sqrt{2 \cdot 9.8 \frac{\text{m}}{\text{s}^2} \cdot 0.4 \text{m} \cdot 13.6} = 10.3 \frac{\text{m}}{\text{s}}$$

Answer: velocity head of water is $10.3 \frac{\text{m}}{\text{s}}$