Siphon applications — a siphon is primarily used for which of the following hydraulic purposes?

Introduction / Context:
A siphon is a closed conduit shaped to rise above the free surfaces of the reservoirs it connects, allowing flow from a higher reservoir to a lower one even when a ridge (hill) lies between them, provided the summit pressure does not drop below vapor pressure significantly.

• Two reservoirs at different elevations with an intervening high point.
• The siphon is initially primed (filled with liquid).
• Atmospheric pressure sustains the liquid column at the summit without cavitation.

Concept / Approach:

Flow occurs due to the net head difference between the reservoirs. The siphon’s summit experiences sub-atmospheric pressure; if the elevation exceeds permissible limits, vaporization can break the siphon. Thus, the classic application is bypassing an obstacle like a hill between reservoirs.

Step-by-Step Solution:

Verification / Alternative check (if short method exists):

Bernoulli analysis between free surfaces demonstrates flow direction and confirms sub-atmospheric summit pressure.

Why Other Options Are Wrong:

Filling a higher tank from a lower by siphon violates energy considerations; ordinary town supply does not require crossing a summit; “none” is incorrect; laminarization is unrelated.

Common Pitfalls (misconceptions, mistakes):

Ignoring priming; placing the summit too high; neglecting air leaks that break siphon action.

Final Answer:

to connect water reservoirs at different levels intervened by a hill