What term describes the loss of pressure due to friction as fluid moves through pipes?

• A. Dynamic pressure
• B. Friction Loss
• C. Static pressure
• D. Velocity

Answer: (B)

The loss of pressure due to friction as fluid moves through pipes is called friction loss. This term captures the energy dissipated as water rubs against the pipe walls and encounters turbulence along the length, reducing the available pressure downstream. In pipe-flow math, friction loss is the h_f term in the energy equation (Bernoulli with losses), which explains why pressure drops as distance increases. It’s different from dynamic pressure, which is the kinetic energy of the moving fluid (0.5 rho v^2); static pressure, which is the energy present when the fluid is stationary; and velocity, which is simply the speed of the fluid rather than a loss component. Friction loss increases with flow rate and depends on pipe diameter, roughness, length, and the fluid’s properties, so it’s the value designers calculate to size pipes and pumps.