Previous Year Papers

Download Solved Question Papers Free for Offline Practice and view Solutions Online.

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.

Mechanical Properties of Fluids

Multiple Choice Questions

71.

Two capillary tubes of different diameters are dipped in water. The rise of water is

the same in both tubes
greater in the tube of larger diameter
greater in the tube of smaller diameter
independent of the diameter of the tube

72.

Mille is an example for

emulsion
inelastic gel
foam
elastic gel

73.

Spheres of iron and lead having same mass are completely immersed in water. Density of lead is more than that of iron. Apparent loss of weight is w₁ for iron sphere and w₂ for lead sphere, Then $\frac{w_{1}}{w_{2}}$ is

> 1
= 1
become 0 and 1
= 0

74.

Two solds P and Q float in water. It is observed that P floats with half of its volume immersed and Q floats with $\frac{2}{3}$ rd of its volume is immersed. The ratio of densities of P and Q is

$\frac{4}{3}$
$\frac{3}{4}$
$\frac{2}{3}$
$\frac{3}{2}$

75.

A flow of liquid is streamline, if the Reynold's number is

less than 1000
greater than 1000
between 2000 to 3000
between 4000 to 5000

76.
An ideal fluid flows through a pipe of circular cross-section with diameters 5 cm and 10 cm as shown in the figure. The ratio of velocities of fluid at A and B is

4 : 1

1 : 4

2 : 1

1 : 2

4 : 1

From continuity equation,

$a_{1} v_{1} = a_{2} v_{2} \frac{v_{1}}{v_{2}} = \frac{a_{2}}{a_{1}} a_{1} = π {(\frac{d_{1}}{2})}^{2} \Rightarrow a_{2} = π {(\frac{d_{2}}{2})}^{2}$

where, d₁ and d₂ are the diameters of the openings.

$\Rightarrow \frac{v_{1}}{v_{2}} = \frac{({πd}_{2}^{2} / 4)}{({πd}_{1}^{2} / 4)} = \frac{d_{2}^{2}}{d_{1}^{2}} = {(\frac{10 cm}{5 cm})}^{2} = \frac{10 \times 10}{5 \times 5} = \frac{4}{1} or = 4 : 1$

77.

'Hydraulic lift' works on the basis of

Stoke's Law
Bernoulli's Law
Pascal's Law
Toricelli's Law

78.

Two non-mixing liquids of densities $straight rho$ and n $straight rho$ (n >1) are put in a container. The height of each liquid is h. a solid cylinder of length L and density d is put in this container. The cylinder floats with its axis vertical and length pL (p<1) in the denser liquid. The density d is equal to,

$open curly brackets 2 plus left parenthesis straight n plus 1 right parenthesis straight p close curly brackets rho$
$open curly brackets 2 plus left parenthesis straight n minus 1 right parenthesis straight p close curly brackets rho$
{1+(n-1)p} $straight rho$
{1+(n-1)p} $straight rho$

3660 Views

79.

The wind with speed 40 m/s blows parallel to the roof of a house. The area of the roof is 250m². Assuming that the pressure inside the house is atmospheric pressure, the force exerted by the wind on the roof and the direction of the force will be( p_air = 1.2 kg/m³)

4.8 x 10⁵ N, downwards
4.8 x10⁵ N , upwards
2.4 x 10⁵ N , upwards
2.4 x 10⁵ N , upwards

3956 Views

80.

A certain number of spherical drops of a liquid of radius r coalesce to form a single drop of radius R and volume V. If T is the surface tension of the liquid, then