Difficulty: Easy
Correct Answer: All of the above
Explanation:
Introduction / Context:
Bernoulli’s equation is derived from the mechanical energy balance for steady, incompressible, inviscid flow along a streamline with no pumps/turbines and only gravity as a body force. Recognizing its assumptions prevents misuse in diffusers, across valves, or in highly viscous flows.
Given Data / Assumptions:
Concept / Approach:
Bernoulli states p/γ + v^2/(2 g) + z = constant along a streamline for the above conditions. In practice, a kinetic energy correction factor may be used if velocity is non-uniform; the “uniform velocity” statement reflects that simplified use without correction factors.
Step-by-Step Solution:
Verification / Alternative check:
Compare with the full energy equation including head loss and pump/turbine head; Bernoulli is the special case with h_L = 0 and h_pump = h_turbine = 0.
Why Other Options Are Wrong:
Options (a), (b), and (c) individually are partial statements; the correct comprehensive assumption set is captured by “All of the above”.
Common Pitfalls:
Applying Bernoulli across components with significant losses or work exchange; ignoring the need for correction factors when velocity is highly non-uniform.
Final Answer:
All of the above
Discussion & Comments