Question

Explain why the liquid from a siphon flows more quickly out of the siphon when the level of the mouth of the siphon is lower 

Answer 1

Bernoulli's equation:

$$0.5\rho v^2=P_{atm}-\rho gh$$

Thus the faster the fluid flows in the siphon, the lower the bend in the tube

must be to maintain siphon flow.