Bubble Rainbow Rings Follow FizzicsEd 150 Science Experiments: Comments 4 You will need Detergent Water Table Salt Plastic bowl Straw Bright torch Copyright Instruction 1 Mix up some bubble mix (water plus detergent plus a sprinkle of salt). 2 Coat the underneath of a plastic bowl with bubble mix, ensuring a coating across the whole surface. 3 Use the straw to blow a bubble on the surface of the bowl. 4 Shine your torch on the bubble from the side. 5 You should see perfect interference rings, especially when you’re looking from below the bubble. 6 School science visits since 2004! – Curriculum-linked & award-winning incursions. – Over 40 primary & high school programs to choose from. – Designed by experienced educators. – Over 2 million students reached. – Face to face incursions & online programs available. – Early learning centre visits too! 7 Online courses for teachers & parents – Help students learn how science really works 8 Get the Unit of Work on Light & Colour here! What is colour addition vs subtraction? What is opacity, translucence & transparency? What is the difference between refraction & reflection? Explore UV light, lenses, thermochromism and more! Includes cross-curricular teaching ideas, student quizzes, a sample marking rubric, scope & sequences & more What is Happening? White light is made up of many colours. These different colours have different wavelengths, beginning with red at 700nm through to violet at 380nm. We can see the many colours of light on bubbles as the bubble surface can break up the white light into the visible colours of the rainbow. Since light has wave properties, it will experience interference (the addition of waves). This interference is like that seen with water waves & ripples that you see when you drop a rock into a pond. We get interference from a thin film like a bubble, because the light waves which bounce off the front and back surfaces of the bubble wall add constructively or destructively. Constructive interference occurs when two identical waves moving in sync meet (they are in phase). The heights of the two waves (the amplitudes) then add together to produce an even taller wave that has the amplitude equal to the sum of the two smaller wave amplitudes. Think of this like building waves on top of each other! You’ll see light coloured rings at these points. Destructive interference happens when two identical waves are moving completely out of sync with each other (when one wave moves upwards the other is moving downwards, thereby being 180 degrees out of phase). The two opposite but identical waves then cancel each other out. Think of this like the trough of one wave being filled by the crest of the other. Here is where you will see darker rings. Whether you get destructive or constructive interference depends on the colour of the light and the thickness of the bubble. The bubble’s thickness is not uniform, that is why you see fringes or bands of different colours, and dark bands where the light interferes destructively. Over time, the thickness of the bubble changes, leading to a changing and swirling of the colours! Variables to test More on variables here Is there any difference if you change the detergent used? What happens when you shine different coloured lights at the bubble? Does the water temperature change anything? Going Further For more details about how wave interference works, check out this explanation from PhET Light & Colour Years 1 to 6 Maximum 30 students Workshop or Show (NSW & VIC) 60 or 90 minutes Online Class Available Read More Enquire Now STEM Full Day Accelerator - Primary Designed from real classroom experiences, this modular day helps you create consistently effective science learning that directly address the new curriculum with easily accessible and cost-effective materials. Read More Enquire Now Rainbow Fireworks Glasses $1.98 inc. GST View Details Add to Cart Trustpilot Prism by Discover Science $10.95 inc. GST View Details Add to Cart Trustpilot
School science visits since 2004! – Curriculum-linked & award-winning incursions. – Over 40 primary & high school programs to choose from. – Designed by experienced educators. – Over 2 million students reached. – Face to face incursions & online programs available. – Early learning centre visits too!
Get the Unit of Work on Light & Colour here! What is colour addition vs subtraction? What is opacity, translucence & transparency? What is the difference between refraction & reflection? Explore UV light, lenses, thermochromism and more! Includes cross-curricular teaching ideas, student quizzes, a sample marking rubric, scope & sequences & more
Light & Colour Years 1 to 6 Maximum 30 students Workshop or Show (NSW & VIC) 60 or 90 minutes Online Class Available Read More Enquire Now
Years 1 to 6 Maximum 30 students Workshop or Show (NSW & VIC) 60 or 90 minutes Online Class Available
STEM Full Day Accelerator - Primary Designed from real classroom experiences, this modular day helps you create consistently effective science learning that directly address the new curriculum with easily accessible and cost-effective materials. Read More Enquire Now
Designed from real classroom experiences, this modular day helps you create consistently effective science learning that directly address the new curriculum with easily accessible and cost-effective materials.
I love this experiment, and the explanation is really in depth and helpful for teens like me. Thank you fizzics! Reply
This website uses cookies to improve user experience. By using our website you consent to all cookies in accordance with our Cookie Policy.
Thank you for looking to subscribing to our newsletter 🙂 Through this service you’ll be first to know about the newest free experiments, science news and special offers. PLUS: Get a free Kitchen Chemistry Booklet with >20 experiments, how to use variables plus a handy template!
Please fill out the details below and an email will be sent to you. Once you get that just click on the link to confirm your subscription and you're all done!