Tag: fundamental and derived units

Questions Related to fundamental and derived units

Which of the following is a fundamental property of a substance?

  1. Density

  2. Mass

  3. Volume

  4. Current


Correct Option: B
Explanation:

The fundamental property of a substance is the property which depends on the body and does not change due to any physical factor. Mass is a fundamental property of a substance. Another such property is the charge.

Define density.

  1. Density of a substance is defined as the weight per unit volume of that substance.

  2. Density of a substance is defined as the mass per unit volume of that substance.

  3. Density of a substance is defined as the volume per unit mass of that substance.

  4. Density of a substance is defined as mass times volume of the substance.


Correct Option: B
Explanation:

Density of a substance is defined as the mass per unit volume. Its SI unit is $kgm^{-3}$. For example, the density of water at room temperature and atmospheric pressure is $1\ kgm^{-3}$.

Which one of the following conditions will cause the density of a liquid to decrease?

  1. Adding more of the liquid to the container

  2. Cooling the liquid

  3. Heating the liquid

  4. Dividing the liquid into two equal volumes


Correct Option: C
Explanation:

$Answer: C$

The density of a liquid or any substance is the material property. The density of the liquid cannot be changed by decreasing the amount of liquid. The density can be effected only by heating the liquid which leads to the change in the molecular distance and leads to a change in density.

Find the odd one out

  1. density

  2. pressure

  3. mass

  4. volume


Correct Option: B
Explanation:

Density, mass, volume are the characterstic property of a substance whereas Pressure is an extensive property which depends on area of application of force.

Density of a material varies with temperature.
  1. True

  2. False


Correct Option: A
Explanation:

Density of the material is defined as mass per unit volume. Since, volume is temperature dependent, increasing the temperature of the material (with few exceptions) decreases the density of material by increasing its volume. 

Hence, given statement is true.

Density of a substance is defined as

  1. Density = Mass x Volume

  2. Density = Mass /Volume

  3. Density = Volume Mass

  4. None


Correct Option: B
Explanation:

Density of the substance is defined as the ratio of mass of substance to its volume.

$\therefore$  Density of substance     $\rho = \dfrac{M}{V}$.

The density of silver is 13.6 times greater than that of water.
  1. True

  2. False


Correct Option: B
Explanation:

We know that, density of silver is $10.5 \times 10^3 \dfrac{kg}{m^3}$ and density of water is $1.00 \times 10^3 \dfrac{kg}{m^3}$.


Therefore, the density of silver is $10.5$ times greater than that of water.

Hence, the given statement is false.

From below substances which is more dense?

  1. Water

  2. Clay

  3. Wax

  4. none


Correct Option: B
Explanation:
The density of the following substances is:
Wax approximately has a density around $900kg/m^3$
The density of water is $1000kg/m^3$
Density of clay is $1330kg/m^3$

The density of the clay is the maximum of all the three.

Which of the following is true about the density of a substance?

  1. It is a derived quantity.

  2. The unit of density in SI system is kilogram per metre$^3$.

  3. The density of a substance can be measured if the mass of the substance for a certain volume is known.

  4. Density is a vector quantity


Correct Option: A,B,C
Explanation:

Let the mass of the substance be $m$ and its volume be $V$. Then the density of the substance is defined as the ratio of mass to the volume of the body.

Thus the density of a substance can be derived as  $\rho = \dfrac{m}{V}$

SI unit of mass is $kg$ and that of the volume is $m^3$. Thus SI unit of density is  $kg/m^3$.
The density of a substance is a scalar quantity, not a vector quantity as it has magnitude only.
Hence options A, B and C are correct.

SI unit of density is ________ times its CGS unit.

  1. 1000

  2. 10

  3. 0.1

  4. 0.001


Correct Option: D
Explanation:

SI unit of density $=\dfrac { kg }{ { m }^{ 3 } } =\dfrac { 1000 }{ 10^6 } \dfrac { g }{ cc } $

                             $\dfrac { 1kg }{ { m }^{ 3 } } ={ 10 }^{ -3 }9/cc$