This type of flowmeter measures the velocity based on the difference between the flow's dynamic pressure and the static pressure

• A. Pitot
• B. Orifice
• C. Venturi
• D. Magnetic

Answer: (A)

A Pitot tube uses the difference between dynamic pressure and static pressure to determine flow velocity. It has a tube facing the flow to capture stagnation (total) pressure and a separate static port to measure the fluid’s static pressure. The difference between stagnation and static pressure equals the dynamic pressure, q = ½ρv². Solving for velocity gives v = sqrt(2(p_t − p_s)/ρ). This direct pressure-difference method yields velocity, which is why a Pitot device is used for measuring how fast the fluid is moving. In contrast, orifice and Venturi meters rely on differential pressure to infer flow rate (not velocity directly), and magnetic meters estimate velocity through electromagnetic principles without using a pressure difference.