Correct Answer - Option 4 : Maximum

**Explanation:**

Efficiency of power transmission is given by

\(\eta = \frac{{H - {H_L}}}{H}\)

For maximum efficiency

\({H_L} = \frac{H}{3}\)

We get

\({\eta _{max}} = \frac{{H - \frac{H}{3}}}{H}\)

ηmax = 66.66%

**Hence when the flow is such that one third of the static head is consumed in pipe friction, the power delivered by the given pipeline will be maximum.**