Have you ever seen water travels? Do you know you can do this really really simple Science experiment at home with really really easily found materials at home?
– 2 cups
– a long string (not a thread or polyester string as it needs to be thick and can absorb water)
– water (of course!)
– scotch tape
– food colouring (optional)
1. Get ready the materials. Dipped the string in the water to get it wet.
2. Use the scotch tape to tape 1 end of the string inside the cup and the other end in the other cup.
2. Half fill 1 cup with water. Don’t get too excited and fill the cup to the brim, otherwise you will need to prepare a mop and mop!
3. Add a little food colouring so that you have a more visible view of how the water travels.
4. Hold the cups far enough apart (string will be straight or slightly bent but not too far to pull off the tape). Top cup is the one with water and bottom cup is empty.
5. Slowly but surely pour the water down towards the bottom cup. Watch what is happening!
The water travels from the top cup to the bottom cup without spilling all over with just a string between the 2 cups. Why? Because a drop of water is made up of gazillion molecules that are held together by electrical, molecular bonds. These molecular bonds are very strong which is why they stick together very well. This is called cohesion.
When the water molecules are attracted to molecules of other objects, such as the string, this is called adhesion. That is why you noticed the water stick to the string when it moves down. Adhesion and cohesion prevented the water from dripping. But if you are pouring too much or too fast, the water will spill due to gravity.
Importance of adhesion and cohesion
Do not underestimate this adhesion and cohesion forces as it has its importance to living things. For example, insects that rely on surface tension to stay afloat on the surface of the water and the movement of the water to the top of the trees.
– Try it out with other liquids such as milk or soda and see if it works the same as water.
– Try it out with different types of strings to explore further with different liquids.
Smarties had an awesome time with the experiment. It was challenging for them as well because they were trying hard not to spill the water all over the place. Psst… they did spill all over the very first time they tried but, of course, they have to clean up on their own. It’s their responsibility, isn’t it? hehe…