Mechanical Properties of FluidsNEET Physics · Class 11 · NCERT Chapter 9

A vessel contains water up to height $h$. The pressure at the bottom (gauge pressure, ignoring atmosphere) is:

In a hydraulic lift, a force of $50\text{N}$ is applied on a small piston of area $10{\text{cm}}^2$. The maximum load lifted on a large piston of area $1000{\text{cm}}^2$ is:

A body of density $0.6$ floats in water. The fraction of its volume above the water is:

A body weighs $50\text{N}$ in air and $40\text{N}$ when fully immersed in water. The buoyant force on it is:

Water flows through a pipe whose cross-section reduces from $10{\text{cm}}^2$ to $2{\text{cm}}^2$. If the speed in the wider section is $1\text{m/s}$, the speed in the narrower section is:

Water flows out of a small hole at depth $h=1.25\text{m}$ below the surface. Take $g=10{\text{m/s}}^2$. The speed of efflux is:

A small steel ball falls through a long column of glycerine. Just after release, its velocity:

The terminal velocity of a small sphere falling through a viscous fluid is proportional to:

The excess pressure inside a soap bubble of radius $r$ is:

Water rises in a capillary tube of radius $r$ to a height $h$. If the same tube is replaced by one of radius $2r$, the new height of rise is:

A wooden block of density $0.8{\text{g/cm}}^3$ floats in oil of density $0.9{\text{g/cm}}^3$. The fraction of the block submerged in the oil is:

According to Bernoulli's principle, in a flowing fluid, regions of higher speed have:

Pascal's law is the basis of:

The equation of continuity is a consequence of:

The unit of surface tension is:

At what depth in seawater (density $1025{\text{kg/m}}^3$, $g=10{\text{m/s}}^2$) does the pressure equal twice atmospheric pressure ($1.013\times 10^5\text{Pa}$)?

Stokes' law for the viscous drag on a small sphere of radius $r$ moving at speed $v$ through a fluid of viscosity $\eta$ is:

Water flows through a horizontal pipe with section $A_1$ and speed $v_1$, then through a constriction with section $A_2<A_1$ and speed $v_2$. Pressure difference $P_1-P_2$ is:

The work done in increasing the radius of a soap bubble from $r$ to $2r$ at constant temperature is (surface tension $T$):

A solid block of mass $m$ is suspended by a spring scale. Half the block is submerged in water (density ${\rho }_w$). The block has volume $V$ and density ${\rho }_b$. The reading on the spring scale is:

Atmospheric pressure is approximately:

Two spheres of the same material but different radii $r$ and $2r$ are dropped through a viscous fluid. The ratio of their terminal velocities is:

In a Venturi meter, the cross-section decreases from $A$ to $A/2$ along a horizontal pipe. If the speed in the wider section is $v$, the pressure drop in the narrower section is:

Water droplets are spherical because:

A solid weighs $30\text{N}$ in air, $20\text{N}$ in water and $24\text{N}$ in another liquid. The relative density (specific gravity) of the second liquid is:

Water enters a horizontal pipe at $4\text{m/s}$ and exits at $1\text{m/s}$. The ratio of cross-sectional areas (entry : exit) is:

In Pascal's principle, pressure applied to an enclosed fluid is transmitted to all parts of the fluid:

An iceberg floats with about $90\%$ of its volume submerged. The density of ice (sea water density 1025 kg/m³) is approximately:

The dimensional formula of surface tension is:

The lift on an aircraft wing is explained by: