MARTYN F. CHILLMAID / SCIENCE PHOTO LIBRARY MARTYN F. CHILLMAID / SCIENCE PHOTO LIBRARY
Thermal expansion of air. A glass, bulb flask being held in someones hands, showing that air expands when heated. The heat from the person's hands warms the air in the flask. As the gas molecules heat up they gain energy enabling them to move around more. This increases the volume of the gas. As the volume increases, the pressure increases and the air is pushed through the tube (left). The air travels down the tube and bubbles out of the end through the water in the beaker (bottom left).
Model release not required. Property release not required.