### Physics - Mechanical Properties of Fluids

#### Question - 1

An ice block with relative density 0.9 floats in water (density=1.0 g/cc). A part of block is outside water level. When the ice block has completely melted, the water level will

• A rise
• B fall
• C remain same
• D it will depend on mass of block

#### Question - 2

A piece of iron has weight win air, w1 when immersed completely in water and w2 when immersed completely in a liquid. The relative density of liquid is

• A $\frac { { w }_{ 1 }-{ w }_{ 2 } }{ w-{ w }_{ 1 } }$
• B $\frac { { w }_{ 1 }-{ w }_{ 2 } }{ w-{ w }_{ 2 } }$
• C $\frac { { w }-{ w }_{ 1 } }{ w-{ w }_{ 2 } }$
• D $\frac { { w }-{ w }_{ 2 } }{ w-{ w }_{ 1 } }$

#### Question - 3

In absence of gravity, which of the following will not be there for a fluid?

• A Viscosity
• B Surface tension
• C Pressure
• D Archimedes' upwards thrust

#### Question - 4

A body is just floating in a liquid. Both have same densities (i.e., body and liquid). If body is slightly pressed down and then released it will

• A oscillate
• B sink down
• C come back to same position instantaneously
• D come back to same position slowly

#### Question - 5

Along streamline,

• A the velocity of a fluid particle remains constant
• B velocity of all fluid particles crossing a given position is constant.
• C the velocity of all fluid particles at a given instant is constant
• D the speed of a fluid particle remains constant

#### Question - 6

A liquid is allowed to flow into a tube of truncated cone shape. Identify the correct statement from the following.

• A Speed is low at wider end
• B Speed is high at narrow end
• C Both (a) and (b) are correct
• D None of the above

#### Question - 7

An ideal fluid flows through a pipe of circular cross - section mad of two sections with diameters 2.5 cm and 3.75 cm. The ratio of velocities in the two pipes is

• A $9:4$
• B $3:2$
• C $\sqrt { 3 } :\sqrt { 2 }$
• D $\sqrt { 2 } :\sqrt { 3 }$

#### Question - 8

A cylinder of radius ris filled with water upto a height h, so that thrust on the walls is equal to that on bottom, then it is equal to

• A $\frac { R }{ 2 }$
• B $R$
• C $\frac { R }{ 3 }$
• D $2R$

#### Question - 9

A sphere of mass m falls through a viscous fluid with the terminal velocity v. Then, the terminal velocity of another sphere curved out of same material but mass 27 m is

• A 3v
• B 6v
• C 27v
• D 9v

#### Question - 10

When a number of small droplets combine to form a large drop, then

• A energy is released
• B energy is absorbed
• C cannot be predicted
• D process does not involve any energy change