BUBBLE WANDS

Bubbles

Bubbles are made out of three layers: two soap layers with a water layer in between. Soap is made out of lipids; it has a hydrophobic (water-hating) tail and a hydrophilic (water loving) head.

Glycerine is an important ingredient in bubble solution. Its found in bubble gum and acts as a surface tensioner.

There is air pressure pushing from outside and inside the bubble. The internal pressure is greater than the pressure pushing from the outside. Smaller bubbles have higher internal pressure than larger ones.

Larger bubbles have a greater "obble." Blow two bubbles of different sizes and see the difference in movement.

Bubbles are spherical because a sphere contains the largest amount of volume with the smallest amount of surface area. When two bubbles of the same volume meet, they form a shared wall in order to decrease surface area. When a smaller bubble meets a larger bubble, the higher internal pressure of the smaller bubble allows it to push into the larger bubble. All bubbles meet the shared wall at an angle of 120 degrees.

Ever see a rainbow bouncing off a bubble? The colors that we see are due to reflection. Light travels through air and hits the bubble. As light enters a different medium it bends and reflects back out. In constructive interference the light waves enforce each other and we are able to see colors. In destructive interference the light waves cancel each other out which is why bubbles or parts of bubbles may seem invisible at times. The alternating dark and light bands of bubbles are caused by constructive and destructive interference.

Bubbles pop for a number of reason with evaporation being the most common. Windy days aren't good for making bubbles because bubbles are much harder to form. Gravity is another reason as it pulls the bubble solution towards the center of the earth causing it to thin and eventually pop. For best results, bubble on a humid day when it's moist.

Wet your hand in bubble solution. Try to hold a bubble in your hand. See what happens!