Rankers Physics

Properties of EM Waves: Practice Problem & Solution

The condition under which a microwave oven heats up a food item containing water molecules most efficiently is: (2013)
Infra-red waves produce heating in a microwave oven
The frequency of the microwaves must match the resonant frequency of the water molecules
The frequency of the microwaves has no relation with natural frequency of water molecules
Microwaves are heat waves, so always produce heating

Solution Explained:

To solve this problem, we apply the core principles of Properties of EM Waves. Understanding the underlying formula is key to arriving at the correct answer below:

Microwave ovens heat food efficiently when the frequency of the microwaves matches the resonant frequency of water molecules, transferring energy via resonance.

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