Expansion and contraction


EXPANSION & CONTRACTION


Expansion:

•      The process in which the volume of a substance increases with the increase in temperature is termed as expansion.

Figure 6- Electric cables expand in summer season

•      Matter increases in volume when there is an increase in temperature.

•      The volume increases the most in case of gases.

•      When something expands; it takes up more space.

Figure 8- Hot air balloon

•      Hot air balloon flies in the air because of the hot air present inside it. Due to this hot air, balloon expands.

 

Exception:

Water expands when cooled or frozen and contracts when warmed or heated.

 

Contraction:

•      The process in which the volume of the substance decreases with the decrease in temperature is termed as contraction.

Figure 9- Electric cables contract in winter season

•      When something contracts; it shrinks.

Figure 10- Hot air balloon

•      Hot air balloon deflates (shrinks) because of the cold air in the atmosphere. Due to this cold air, balloon contracts.