A hydraulic ram (hydram) is a classic water-supply device used where a small fall of water can lift a portion of that water to a higher elevation. Which statement best describes what a hydraulic ram is designed to do in practical field applications?

Introduction / Context:
A hydraulic ram (hydram) is a water-powered pump widely used in rural water-supply engineering. It exploits the momentum of a relatively large flow at low head to lift a smaller quantity of water to a much greater head, requiring no electricity or fuel.

Given Data / Assumptions:

• Continuous source of water with a modest supply head (fall).
• Desire to lift a fraction of that water to a higher elevation.
• No electrical or combustion power source available onsite.

Concept / Approach:
The hydram uses the water hammer effect. When a waste valve suddenly closes, the momentum of the moving water generates a pressure rise that opens a delivery check valve, forcing part of the water into an air-charged delivery chamber and up the delivery pipe to a higher level.

Step-by-Step (Principle of Operation):
Water flows down the drive pipe under supply head (Hs), building velocity.Waste valve initially open discharges water to atmosphere; flow accelerates.Waste valve slams shut due to increased dynamic pressure, creating a high transient pressure (water hammer).The transient opens the delivery check valve; water enters the air chamber and delivery pipe against a higher static head (Hd).Pressure decays; delivery valve closes; waste valve reopens; the cycle repeats automatically.

Verification / Alternative Check:
Energy balance shows that (flow lifted * Hd) is less than (supply flow * Hs); overall efficiency often 50%–70% for well-designed systems. No external power is required beyond the water source itself.

Why Other Options Are Wrong:
Accelerate water for dissipation: not the purpose; acceleration is a means to create a pressure pulse, not an end.Lift heavy loads: that describes hydraulic jacks, not hydrams.None of these / vacuum priming: incorrect; the defining function is power-free water lifting.

Common Pitfalls:

• Assuming constant flow; hydram operation is cyclic.
• Confusing hydram with conventional pumps that need external power.
• Ignoring the need for a proper drive pipe length and rigid support to harness water hammer safely.

Final Answer:
lift water to a higher elevation without using an electric motor or external power