What is the main difference between electromagnetic wave theory and Planck's quantum theory ?

Explanation

**Step-by-Step Solution:**

1. **Understanding Electromagnetic Wave Theory:**
- Electromagnetic wave theory posits that energy is emitted or absorbed in a continuous manner. This means that the energy can take on any value within a range, similar to how a wave can have any amplitude or frequency.

2. **Understanding Planck's Quantum Theory:**
- In contrast, Planck's quantum theory introduces the concept that energy is emitted or absorbed in discrete packets called "quanta." This means that energy can only exist in specific, quantized amounts rather than any arbitrary value.

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