Dispersion and Colour
Dispersion splits white light into the colours of the spectrum because each colour refracts by a different amount.
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Dispersion splits white light into the colours of the spectrum because each colour refracts by a different amount.
- Red bends least and violet most
- Rainbows form from refraction in raindrops
- Coloured objects reflect their own colour
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Dispersion and Colour?
Within Physics, which covers forces, energy, waves, electricity, magnetism, light and space explained through motion and experiments, this topic explains Dispersion and Colour. Physics topics explain how things move, push, heat up and carry energy, so each one here pairs a definition with a live model you can change.
Check that you can explain Dispersion and Colour in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Dispersion and Colour explains how the physical world behaves, from sport and transport to electricity and medicine.
Dispersion and Colour in detail
Dispersion is the splitting of white light into its component colours, the spectrum, which happens in a prism because each colour is refracted by a different amount, with violet bending most and red least. Rainbows form by refraction and internal reflection in water droplets.
Objects have colour because they reflect some wavelengths and absorb others: a red object reflects red light and absorbs the rest. Under coloured light, objects can look different. The primary colours of light are red, green and blue, and mixing them gives white. Filters transmit only certain colours.
How the interactive helps you understand Dispersion and Colour
Watch the light rays in the interactive. Use any sliders or buttons it offers to change the values and see how the light rays responds.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of Dispersion and Colour.
Real-life uses and examples
- Answer “explain” questions by linking Dispersion and Colour to a clear cause and effect.
- Predict what a ball, car or circuit will do with Dispersion and Colour before you do the calculation.
- Explain everyday devices, such as brakes, lifts or chargers, using Dispersion and Colour.
Common mistakes to avoid
- Forgetting that some quantities, such as force or velocity, also have a direction.
- Mixing up Dispersion and Colour with a related quantity that has different units.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Dispersion and Colour
What is Dispersion and Colour?
Dispersion splits white light into the colours of the spectrum because each colour refracts by a different amount.
What are the most important points about Dispersion and Colour?
The main points are: Red bends least and violet most; Rainbows form from refraction in raindrops; Coloured objects reflect their own colour.
Why is Dispersion and Colour useful?
Understanding Dispersion and Colour explains how the physical world behaves, from sport and transport to electricity and medicine.
How can I practise Dispersion and Colour?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to Dispersion and Colour?
Related topics in Physics include Static Electricity, Resistance and Ohm's Law, Components: Resistors, LDRs and Thermistors.