There is nothing like conducting experiments on your own to understand how certain scientific principles work. Here are two easy to conduct experiments that will be fun for your homeschool students to perform.
The Concept of Evaporation
Take two kitchen sponges of the exact same size. Place them on a plate and pour equal amounts of measured water onto them. Place one sponge under the glare of a lamp. Place the other under the draft of an electric table fan. Take a guess on which one will dry the sponge first.
Now measure the amount of time taken by both sponges to become absolutely dry again. Which of the two – heat or wind – worked faster for evaporation to occur. Was your guess correct? To add a variant to the experiment you can use both heat and wind to see how the time taken for evaporation in the sponges will be under both influences. Is the time shorter now? Or did it take longer. Keep playing with the variables and see how evaporation occurs under different circumstances.
Rising Heat Currents
This here is a simple experiment but will need adult supervision. Take a transparent, large glass beaker. Fill it with cold tap water with about one fourth of the top still empty. Now heat some water and add it to a smaller glass jar which is less than half the size of the other one. Now add some food colour to the hot water and seal it with a plastic cover. Now put the small jar inside the large beaker gently.
Remove the plastic cover as gently as you can without disturbing the water inside the small jar. As the convection current carries the hot water to the surface of the larger beaker you will be able to get a visual confirmation of the hot currents rising up over the cold tap water. The swirls are not only pretty to look at but also prove the scientific principle of hot air rising above cold water. Make sure that your homeschool students have the camera ready to take some special pictures and videos.
