Difficulty: Easy
Correct Answer: Potential head, kinetic head, and pressure head
Explanation:
Introduction / Context:Bernoulli’s equation is foundational in fluid mechanics for relating pressure, velocity, and elevation along a streamline in steady, inviscid, incompressible flow. It states that the total mechanical energy per unit weight (total head) remains constant, barring losses or addition of energy.
Given Data / Assumptions:
Concept / Approach:The total head H is written as H = z + p/(ρ g) + V^2/(2 g), where z is potential (elevation) head, p/(ρ g) is pressure head, and V^2/(2 g) is velocity (kinetic) head. These components sum to a constant in an ideal flow without losses.
Step-by-Step Solution:
Potential head = elevation term z.Pressure head = p / (ρ g).Kinetic head = V^2 / (2 g).Total head = z + p/(ρ g) + V^2/(2 g).Verification / Alternative check:Units check: each term has units of length (metres of fluid), confirming all are “heads.” Including losses would add h_f on the right-hand side to balance real systems.
Why Other Options Are Wrong:
Common Pitfalls:Confusing pressure head with pressure; forgetting to divide by ρ g; mixing energy per unit mass with energy per unit weight; ignoring head losses in real pipelines.
Final Answer:Potential head, kinetic head, and pressure head
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