Two water pipes P and Q having diameter 2× 10- 2 m and 4× 10- 2 m respectively are joined in series with the main supply line of water. The velocity of water flowing in pipe P is

Question

Two water pipes P and Q having diameter 2× 10- 2 m and 4× 10- 2 m respectively are joined in series with the main supply line of water. The velocity of water flowing in pipe P is (A) 4 times that of Q (B) 2 times that of Q (C) 1/2 times that of Q (D) 1/4 times that of Q

Tardigrade Admin · Accepted Answer

Using theorem of continuity, we have π Dp2vp=π DQ2vQ; vp=((DQ/DP))2vQ=((4 × (10)- 2/2 × (10)- 2))2× vQ=4vQ

Q. Two water pipes $P$ and $Q$ having diameter $2 \times 1 0^{- 2} m$ and $4 \times 1 0^{- 2} m$ respectively are joined in series with the main supply line of water. The velocity of water flowing in pipe $P$ is

4 times that of Q

2 times that of Q

1/2 times that of Q

1/4 times that of Q

Using theorem of continuity, we have
$π D_{p}^{2} v_{p} = π D_{Q}^{2} v_{Q};$
$v_{p} = (\frac{D _{Q}}{D _{P}})^{2} v_{Q} = (\frac{4 \times ( 10 ) ^{- 2}}{2 \times ( 10 ) ^{- 2}})^{2} \times v_{Q} = 4 v_{Q}$

Q. Two water pipes P and Q having diameter 2×10−2m and 4×10−2m respectively are joined in series with the main supply line of water. The velocity of water flowing in pipe P is