# GATE Papers >> Mechanical >> 2015 >> Question No 232

Question No. 232

Three parallel pipes connected at the two ends have flow-rates Q1, Q2 and Q3 respectively, and the corresponding frictional head losses are hL1, hL2 and hL3 respectively. The correct expressions for total flow rate (Q) and frictional head loss across the two ends (hL) are

##### Answer : (B) (B) Q=Q1+Q2+Q3; hL=hL1=hL2=hL3

Solution of Question No 232 of GATE 2015 Mechanical Paper

$From\;fig\;\;Q=Q_1+Q_2+Q_3$

and we know that h=$\frac{\triangle P}{\rho g}$

As such $\triangle P\;is\;small\;for\;all\;3\;pipes$

$hL=hL_1=hL_2=hL_3$