Hydraulic Machines MCQ with answer and solution

Concept

Manometric head is the total head that a pump must produce to meet the external requirements (static lift + losses + exit velocity head).

Formula

H_m = h_s + h_d + h_fs + h_fd + V_d²/(2g)

Step-by-step solution

1. Static head = only the vertical lift (suction + delivery height). 2. Suction head = only the suction side part. 3. The pump must overcome static lift, pipe friction losses and give exit velocity head. 4. This total head the pump must produce is the manometric head.

Explanation

Manometric head is the head against which the pump works. It includes static lift, friction losses in the pipes and the velocity head at outlet. So the head the pump must produce for external needs is the manometric head.

Why the other options are wrong

B: Dynamic head is a general term, not the standard name for this definition. C: Suction head is only the suction side part of the total head. D: Static head is only the vertical height and ignores losses.

Shortcut

Pump 'total head to satisfy external requirement' = manometric head.

Common mistake

Choosing static head and forgetting friction losses and velocity head.