How does a change in surface tension affect forces on an object?
Have you ever woken up early in the morning and gone outside to find little beads of water perched on the tips of blades of grass? Why doesn’t the water fall off? You might also think of the water strider insect, which seemingly skates atop the surface of the water with ease. These instances are possible due to surface tension, which is the tendency for the surface of a liquid to be strong. What changes occur when the surface tensions of two different liquids are combined? We will seek out the answer to this tense question in the following experiment.
Much of what we now know about surface tension was discovered by the scientist, Agnes Pockels, who was an early pioneer of “surface science.” She did experiments in the sink of her own kitchen and made many important observations that influenced how we study liquids. Surface tension is not only important for many engineering processes - it is also important to the health of the planet, as it allows for the formation of bubbles, which help distribute organic material throughout the layers of the ocean. Today we’re going to do an experiment that will help us better understand how surface tension can be altered with soap and water.
This experiment was selected for Science at Home because it teaches NGSS Disciplinary Core Ideas, which have broad importance within or across multiple science or engineering disciplines.
Learn more about how this experiment is based in NGSS Disciplinary Core Ideas.