Download App

9.1 , fluid mechanics — Physics STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 SciencePhysics9.1 , fluid mechanics1 Mark
MCQ
A cube of external dimension $10\  cm$ has an inner cubical portion of side $5\  cm$ whose density is twice that of the outer portion. If this cube is just floating in a liquid of density $2\  g/cm^3$, find the density of the inner portion
  • A
    $\frac{8}{9}\ gm/cc$
  • B
    $\frac{16}{9}\ gm/cc$
  • ✓
    $\frac{32}{9}\ gm/cc$
  • D
    $\frac{5}{4}\ gm/cc$
✓

Answer

Correct option: C.
$\frac{32}{9}\ gm/cc$
c
$m g=2 \rho_{1} \times 10^{3}+\rho_{1} \times\left(20^{3}-10^{3}\right)$

$=9 \rho_{1} \times 10^{3} \mathrm{g}=\rho \times 8 \times 10^{3} \mathrm{g}$

$\Rightarrow \rho_{1}=\frac{8}{9} \mathrm{gm} / \mathrm{cc}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q (1 Marks)" from 9.1 , fluid mechanics→9.1 , fluid mechanics — all question types→Physics STD 11 Science question papers→Gujarat Board STD 11 Science question papers→Gujarat Board question paper generator→

Similar questions

The distribution of relative intensity $I (\lambda)$ of blackbody radiation from a solid  object versus the wavelength $\lambda$ is shown in the figure. If the Wien displacement law  onstant is $2.9 × 10^{-3}\  mK$, what is the approximate temperature of the object ....... $K$
→
Two objects $A$ and $B$ each of mass $m$ are connected by a light inextensible string. They are restricted to move on a frictionless ring of radius $R$ in a vertical plane (as shown in fig). The objects are released from rest at the position shown. Then, the tension in the cord just after release is
→
Gravitational potential difference between surface of a planet and a point situated at a height of $20\,m$ above its surface is $2\,joule/kg$. If gravitational field is uniform, then the work done in taking a $5\,kg$ body of height $4\,meter$ above surface will be ........ $J$
→
The coordinates of a moving particle at any time $‘t’$ are given by $ x = \alpha t^3$ and $y = \beta t^3$. The speed of the particle at time $‘t’$ is given by
→
A bomb of mass $30\,kg$at rest explodes into two pieces of masses $18\,kg$ and $12\,kg$. The velocity of $18\,kg$ mass is $6\,m{s^{ - 1}}$. The kinetic energy of the other mass is ....... $J$
→
The length, tension, diameter and density of a wire $B$ are double than the corresponding quantities for another stretched wire $A$. Then.
→
A $2100 W$ continuous flow geyser (instant geyser) has water inlet temperature $= 10^o C$ while the water flows out at the rate of $20\,\, g/sec$. The outlet temperature of water must be about ....... $^oC$ 
→
The area under the velocity time graph between any two instants $t = t_1$ and $t = t_2$ gives the distance covered in a time $\Delta\text{t}=\text{t}_2-\text{t}_1:$
→
A point mass oscillates along the x-axis according to the law $x=x_0cos$$\left( {\omega t - \frac{\pi }{4}} \right)$ If the acceleration of the particle is written as $a=Acos$$\left( {\omega t + \delta } \right)$ then
→
A block of mass $m$ is lying on an inclined plane. The coefficient of friction between the  plane and the block is $\mu$. The force $(F_1)$ required to move the block up the  inclined plane will be
→