Question

How many colours are there in white light?

• A. 1
• B. 3
• C. 5
• D. 7

Hint:

Mnemonic for 7 colours of spectrum: VIBGYOR = Violet, Indigo, Blue, Green, Yellow, Orange, Red.

Answer 1

The Correct Option is D

Step 1: Concept of White Light:
White light is a combination of multiple colours of light that can be separated by dispersion (passing through a prism). Step 2: Newton’s Prism Experiment:
Isaac Newton showed that white light splits into a spectrum of 7 colours when passed through a glass prism. This is called the VIBGYOR spectrum. Step 3: Colours in White Light:
The seven colours are: \[ \text{Violet, Indigo, Blue, Green, Yellow, Orange, Red} \]
Step 4: Final Answer:
White light contains 7 colours.