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The frequency of microwave used by a microwave oven to cook food or warm it up is

Asked in GUJCET 2013 · Uses and atmospheric effects

Answer: (4) 0.915 GHz

Step-by-step solution

Idea: an oven must work inside a band set aside for industrial, scientific and medical heating, so that the power leaking out of it does not interfere with communication.

Two microwave allocations are used for heating food: 0.915 GHz (that is 915 MHz) and 2.45 GHz.

Microwaves of these frequencies are absorbed strongly by the water molecules in the food, whose rotational energy they raise, so the food heats from the inside.

Of the four frequencies offered, only 0.915 GHz is such an allocated heating band.

So the frequency used is 0.915 GHz.

Why the other options are wrong

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