Air streams horizontally past an air plane. The speed over the top surface is $60 \,m / s$ and that under the bottom surface is $45 \,m / s$. The density of air is $1.293 \,kg / m ^3$, then the difference in pressure is ....... $N / m ^2$
Medium
Download our app for free and get started
(a)
Applying Bernoullis equation
$P_1+\rho g h+\frac{1}{2} \rho v_1^2=P_2+\rho g h+\frac{1}{2} \rho v_2^2$
$\frac{1}{2} \times \rho\left[v_1^2-v_2^2\right]=P_2-P_1=\Delta P$
$\Rightarrow \frac{1}{2} \times 1.293\left[(60)^2-(45)^2\right]=\Delta P$
$\Rightarrow 1018 \,N / m ^2 \simeq \Delta P$
Download our appand 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
- 1Two vessels $A$ and $B$ have the same base area and contain water to the same height, but the mass of water in $A$ is four times that in $B$. The ratio of the liquid thrust at the base of $A$ to that at the base of $B$ isView Solution
- 2A solid sphere of density $\eta$ $( > 1)$ times lighter than water is suspended in a water tank by a string tied to its base as shown in fig. If the mass of the sphere is m then the tension in the string is given byView Solution
- 3According to Bernoulli's equation $\frac{P}{{\rho g}} + h + \frac{1}{2}\,\frac{{{v^2}}}{g} = {\rm{constant}}$ The terms $A, B$ and $ C$ are generally called respectively:View Solution
- 4Two immiscible liquids $A$ and $B$ are kept in an U-tube. If the density of liquid $A$ is smaller than the density of liquid $B$, then the equilibrium situation isView Solution
- 5A hot air balloon is carrying some passengers, and a few sandbags of mass $1 kg$ each so that its total mass is $480 kg$. Its effective volume giving the balloon its buoyancy is $V$. The balloon is floating at an equilibrium height of $100 m$. When $N$ number of sandbags are thrown out, the balloon rises to a new equilibrium height close to $150 m$ with its volume $V$ remaining unchanged. If the variation of the density of air with height $h$ from the ground is $\rho(h)=\rho_0 e^{-\frac{h}{h_0}}$, where $\rho_0=1.25 kg m ^{-3}$ and $h _0=6000 m$, the value of $N$ is. . . . .View Solution
- 6Different heads are in Column - $\mathrm{I}$ and its formulas are given in Column - $\mathrm{II}$. Match them appropriately.View Solution
Column - $\mathrm{I}$ Column - $\mathrm{II}$ $(a)$ Velocity head $(i)$ $\frac{P}{{\rho g}}$ $(b)$ Pressure head $(ii)$ $h$ $(iii)$ $\frac{{{v^2}}}{{2g}}$ - 7A air bubble rises from bottom of a lake to surface. If its radius increases by $200 \%$ and atmospheric pressure is equal to water coloumn of height $H$. then depth of lake is ..... $H$View Solution
- 8A $U-$ tube containing a liquid moves with a horizontal acceleration a along a direction joining the two vertical limbs. The separation between these limbs is $d$ . The difference in their liquid levels isView Solution
- 9$Assertion :$ The pressure of water reduces when it flows from a narrow pipe to a wider pipe.View Solution
$Reason :$ Since for wider pipe area is large, so flow of speed is small and pressure also reduces proportionately. - 10Consider a solid sphere of radius $\mathrm{R}$ and mass density $\rho(\mathrm{r})=\rho_{0}\left(1-\frac{\mathrm{r}^{2}}{\mathrm{R}^{2}}\right), 0<\mathrm{r} \leq \mathrm{R} .$ The minimum density of a liquid in which it will float isView Solution