Question

What happens when a solid is heated, it:
A. Expands proportionally to the change in temperature.
B. Contracts proportionally to the change in temperature.
C. Expands inversely proportional to the change in temperature
D. Contracts inversely proportional to the change in temperature
E. Does not expand or contract

Answer 1

Hint: To solve this theoretical question, we should know about the thermal expansion of solid. Solid can be expanded linearly, superficially and volumetrically. When any matter is heated it is not required that those particular matters expand or contract in this way, we will decide which option is the correct one.

Complete step by step solution:
Option A.
Expands proportionally to the change in temperature.
When the matter is heated without change in its state, it usually expands. According to atomic theory of matter, asymmetry in the potential energy curve is responsible for thermal expansion.
As the temperature rises, the amplitude of vibration increases, as does the energy of the atoms, and hence the average distance between the atoms. So, matter as a whole expands. Because intermolecular force is greatest in gases, thermal expansion is lowest in solids and highest in gases. Solids can expand in one dimension (linear expansion), two dimensions (superficial expansion), and three dimensions (volume expansion), although liquids and gases typically experience just volume changes.
Option B.
Contracts proportionally to the change in temperature.
At first what this option says to us is that, when we heat the solid the solid contracts proportionally to the change in temperature meaning the solid contracts with the increase in temperature.
As we know that the solids expand with the increase in temperature(heating) so we can say that this option is not true.
Option C.
Expands inversely proportional to the change in temperature
Again, what this option says to us is that, when we heat the solid the solid expands inversely proportional to the change in temperature meaning the solid expands when the temperature is decreased.
Explanation to this option is the same as above: that solids expand with the increase in temperature so we can say that this option is not true.
Option D.
Contracts inversely proportional to the change in temperature
Again, what this option says to us is that, when we heat the solid the solid contracts inversely proportional to the change in temperature means the solid gets contracted when the temperature is decreased.
This option also does not make sense as on heating the temperature will increase not decreased so this option is also not true.
Option E.
Does not expand or contract
As on heating a solid it expands so partially this option is true as well as wrong because it is mentioned that on heating it contracts so this option is also not true.
Hence the correct answer: A

Note:
Most materials expand when their temperature is increased. Railway tracks, bridges, all have some means of compensating for thermal expansion. When a homogeneous object increases. Expanded object is like a photographic enlargement. Almost all three states of matter usually expand as their temperature increases. Gases also expand if allowed.