Fill in the following blanks with suitable words :
When a beam of white light is passed through a glass prism, it splits to form lights of __________ colours.

Answer

To fill in the blank in the statement, we need to identify how many colors a beam of white light splits into when it passes through a glass prism.

**Step-by-Step Solution:**

1. **Understanding White Light**: White light is made up of multiple colors. When it passes through a prism, it can be separated into these colors.

2. **Identifying the Prism's Role**: A glass prism refracts (bends) the light as it passes through. This bending causes the different colors in white light to spread out.

3. **Counting the Colors**: The spectrum of colors that white light splits into consists of seven distinct colors. These colors are commonly remembered by the acronym ROYGBIV, which stands for:
- Red
- Orange
- Yellow
- Green
- Blue
- Indigo
- Violet

4. **Filling in the Blank**: Based on the above information, we can fill in the blank in the statement. The complete statement will read: "When a beam of white light is passed through a glass prism, it splits to form lights of **7** colors."

**Final Answer**: 7

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