Two water pipes $P$ and $Q$ having diameter $2 \times 10^{-2} \,m$ and $4 \times 10^{-2} \,m$ respectively are joined in series with the main supply line of water. The velocity of water flowing in pipe $P$ is ........
Medium
Download our app for free and get startedPlay store
(a)

Rate of flow through both pipes will be same

$\text { i.e., } Q_1=Q_2$

$\frac{V_1}{t}=\frac{V_2}{t}$

$\frac{\pi r_1^2 l_1}{t}=\frac{\pi r_2^2 l_2}{t}$

$\left(\text { Where } \frac{l_1}{t}=V_P \text { and } \frac{l_2}{t}=V_Q\right)$

$\Rightarrow \frac{\pi d_1^2}{4} V_P=\frac{\pi d_2^2}{4} \times V_Q$

$\Rightarrow V_P=\left(\frac{d_2}{d_1}\right)^2 V_Q$

$\Rightarrow V_P=\left(\frac{4 \times 10^{-2}}{2 \times 10^{-2}}\right)^2 V_Q$

$V_P=4 V_Q$

art

Download our app
and get started for free

Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*

Similar Questions

  • 1
    A river gradually deepens, from a depth of $4 \ m$ to a depth of $8\  m$ as shown. The width, $W$, of the river does not change. At the depth of $4 \ m$, the river's speed is $12\  m/sec.$ Its  elocity at the $8\  m$ depth is ......... $m/sec$
    View Solution
  • 2
    A log of wood of mass $120 Kg$  floats in water. The weight that can be put on the raft to make it just sink, should be ....... $Kg$ (density of wood = $600 Kg/m^3$)
    View Solution
  • 3
    A submarine experiences a pressure of $5.05\times 10^6\,Pa$ at a depth of $d_1$ in a sea. When it goes further to a depth of $d_2,$ it experiences a pressure of $8.08\times 10^6\,Pa.$ Then $d_2 -d_1$ is approximately ........ $m$ (density of water $= 10^3\,kg/m^3$ and acceleration due to gravity $= 10\,ms^{-2}$ )
    View Solution
  • 4
    Water flows out of the hole on the side of a bucket and follows a parabolic path. If the bucket falls freely under gravity, ignoring air resistance, the water flow
    View Solution
  • 5
    Diagram shows a jar filled with two non mixing liquids $1$ and $2$ having densities ${\rho _1}$ and  ${\rho _2}$  respectively. A solid ball, made of a material of density  ${\rho _3}$ , is dropped in the jar. It comes to equilibrium in the position shown in the figure. Which of the following is true for ${\rho _1}$ ,  ${\rho _2}$ and ${\rho _3}$  ?
    View Solution
  • 6
    A rectangular block is $5 cm × 5 cm × 10cm$  in size. The block is floating in water with $ 5 cm $ side vertical. If it floats with $10 cm $ side vertical, what change will occur in the level of water?
    View Solution
  • 7
    When a rubber ball is taken to a depth of $......\,{m}$ in deep sea, its volume decreases by $0.5\, \%$

    (The bulk modulus of rubber $=9.8 \times 10^{8}\, {Nm}^{-2}$ Density of sea water $=10^{3} {kgm}^{-3}$

    $\left.{g}=9.8\, {m} / {s}^{2}\right)$

    View Solution
  • 8
    A solid sphere of specific gravity $27$ has a concentric spherical cavity and it just sinks in water. The ratio of cavity radius to that of outer radius of sphere is
    View Solution
  • 9
    If the atmospheric pressure is $P_a$, then the pressure $P$ at depth $h$ below the surface of liquid of density $\rho $ open to the atmosphere is
    View Solution
  • 10
    A pressure-pump has a horizontal tube of cross-sectional area $10\,cm ^{2}$ for the outflow of water at a speed of $20\,m / s$. The force exerted on the vertical wall just in front of the tube which stops water horizontally flowing out of the tube, is $...N$ [given : density of water $=1000\,kg / m ^{3}$ ]
    View Solution