This question was previously asked in

MP Sub Engg Official Civil Paper Held on 9th July 2017 - Shift 2

Option 4 : V = C_{v}√2 gh

SSC JE ME Full Test 4

5572

200 Questions
200 Marks
120 Mins

**Concept:**

Pitot Tube is a device that is used to measure velocity at a particular point.

Basic Principle: When we insert a pitot tube at any point

- The velocity of flow at that point reduces to zero, which is called the stagnation point (No motion).
- Kinetic Energy at that point is converted into Pressure Energy, and by measuring the pressure energy at this point, the velocity of flow can be calculated.

**Calculations:**

**Given:**

\(\frac{{{p_1}}}{\gamma }\; + \frac{{V_1^2}}{{2g}} + {z_1} = \;\frac{{{p_2}}}{\gamma }\; + \;{z_2} + h\)

Since piezometric head at point 1 and 2 is the same, i.e.

\( \frac{{{p_1}}}{\gamma } + \;{z_1} = \;\frac{{{p_2}}}{\gamma }\; + \;{z_2}\)

\( \frac{{V_1^2}}{{2g}} = h\)

\( {V_1} =\sqrt {2gh} \)

\( {V_{actual}}=C_v \;\sqrt {2gh} \)

(Cv = coefficient of velocity = 0.98 for pitot tube)