Question

Two cubes, one silver and one iron, have the same mass and temperature. A quantity Q of heat is removed from each cube. Which of the following properties cause the final temperature of the cubes to be different?
A) Density
B) Specific heat
C) Volume
D) Mass

Answer 1

Hint: We need to understand the relation between the mass, the temperature and the heat removed from a system with the other physical quantities which may affect the amount of heat such as the density, specific heat capacity of the volume.

Complete answer:
We know that the heat that can be removed from a material of a particular mass is dependent on the specific heat capacity of the material. The specific heat capacity is defined as the energy required for a material to raise its temperature by one degree Celsius at the optimal conditions of pressure.
This quantity, the specific heat is a characteristic property of each material. It is a material property and therefore, is not related to the mass or the density of the material used.
The heat removed or absorbed from a substance of mass ‘m’ and specific heat capacity ‘s’ which results in a change in temperature from \[{{T}_{1}}\text{ to }{{T}_{2}}\] is given as –
\[\begin{align}
  & Q=ms({{T}_{1}}-{{T}_{2}}) \\
 & \therefore Q=ms\Delta T \\
\end{align}\]
We understand from the relation that the heat involved in changing the temperature of a substance is dependent on the mass, specific heat capacity and the change in temperature of the substance.
For two different substances of equal mass and temperature, the heat involved can be different as the specific heat is different.
Here, the specific heat of iron and silver are different.

The correct answer is B.

Note:
We should be careful while dealing with heat involved in different substances. Here, the mass is given as constant, but in cases when the volume is given, especially for fluids, we need to consider the density to find the mass occupied by the volume.