Question

Microwave oven act on which principle?

• A. Giving rotational energy to water molecules
• B. Giving translational energy to water molecules
• C. Giving vibrational energy to water molecules
• D. Transferring electrons from lower to higher energy levels in water molecules

Answer 1

The correct option is C

Giving vibrational energy to water molecules

Microwave oven

1. Microwave ovens pass microwave radiation through the food that produces heat in it.
2. Water molecules are electric dipoles means it has a partial positive charge at one end and a partial negative charge at the other end.
3. The microwave provides radiations of the frequency $2.45GHz$. They are non-ionizing electromagnetic waves and thus cannot ionize the water molecules present.
4. So, the water molecules absorb energy from the electromagnetic waves. This results in an increase in the temperature of the water.
5. Therefore, the water molecules undergo vibrational motion and transfer energy among them. This energy is heat.
6. Water, fats, and other substances in food absorb microwave energy.

Thus, the microwave oven acts on the principle of giving vibrational energy to the water molecules.

Hence, option C is correct.