Super Soapy Boat
This week we are sharing with you another super easy experiment, called Super Soapy Boat. This is a fun and simple experiment that will further your exploration with surface tension. With an index card, you make a boat that will zoom across the water, and all you will have to do is squeeze a drop or two of liquid dish soap.
Check it out in action!
What you will need:
Index card (3×5 inch index card or piece of a manila file)
Sink (or large container)
Liquid Dish Detergent
What to do:
- First, draw an outline of a rowboat on the index card (pointed at one narrow end, squared off at the other end).
- Next, cut out your boat, adding a small square notch in the center of the squared end.
- Then, fill the sink or large container half way (make sure the sink or container is clean beforehand with no soap or dirt left in it if you have to redo the experiment like we did make sure you clean and put fresh water when you try again).
- Next, place the boat gently on top of the water at one end of the sink.
- Then, squeeze a drop or two of the dish detergent into the space where you cut the notch out of the end of the boat.
- Make sure you write down what happens in your journal and draw a picture.
How it works
At first, the boat sits on top of the water without moving. The tiny molecules that make up the water stick together very tightly, so they form a kind of “invisible skin” on the top of the water which holds the boat in place. This “invisible skin” is called surface tension. When you add the dish detergent, the detergent breaks up the surface tension and the boat zooms ahead.