Fill in the following blanks with suitable words :
White light is composed of __________ colours.

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks how many colors make up white light.

2. **Recall the Concept**: White light is made up of different colors. This is a fundamental concept in physics related to light and optics.

3. **Identify the Colors**: The seven colors that compose white light are:
- Red
- Orange
- Yellow
- Green
- Blue
- Indigo
- Violet

4. **Count the Colors**: By counting the colors listed, we find that there are a total of 7 colors.

5. **Fill in the Blank**: Therefore, the answer to the question is that white light is composed of **7** colors.

**Final Answer**: White light is composed of **7** colors.

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