Objective: To simulate thunder and in doing so, learn why and how it happens in Earth’s atmosphere.
Standards: Structure of the Earth System (atmospheric composition and properties at different elevations; clouds-formation and impact on weather and climate), Energy in the Earth System (heating of earth’s surface and atmosphere drives weather; global weather and climate as influenced by cloud cover and mountain ranges), Position and Motion of Objects (sound is produced by vibrating objects), and Conservation of Energy and Increase in Disorder (heat consists of random vibrations and motions of atoms and molecules).
Materials: One balloon or lunch – sized paper bag.
(1) Blow up the balloon or paper bag.
(2) Close the balloon or bag by tying it with a rubber band or piece of string.
(3) Place one hand on top and one hand on bottom of the balloon or bag and pop it.
Science Behind It: The resulting sound is analogous to thunder. Thunder is created by causing a parcel of air to move very quickly. Thunder stems from a lightning strike because as the lightning flashes through the sky, it heats the surrounding air and forces it to expand rapidly. This movement of expanding air is what produces the sound of thunder. Sound is produced from an object when it vibrates. In areas where there is heavy cloud cover, mountains, or other large obstructions, the sound of thunder may be more pronounced as in these settings it has more and larger objects to bounce its vibrating sound waves off of, thus creating more of an echo.