Why does microwave oven heats up a food item containing water molecules most efficiently?

Explanation

To understand why a microwave oven heats food items containing water molecules most efficiently, we can break down the explanation into several key steps:

### Step-by-Step Solution:

1. **Understanding Microwaves**: Microwaves are a type of electromagnetic wave that operates at a specific frequency range, typically around 2.45 GHz for microwave ovens. These waves are capable of penetrating food items and causing molecular vibrations.

2. **Resonant Frequency of Water Molecules**: Water molecules have a specific resonant frequency at which they can absorb energy. This frequency corresponds to the energy levels of the molecular vibrations of the water.

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