Question
Write a short note on Micro waves.
✓
Answer
→Micro waves (short-wavelength radio waves), with frequencies in the giga hertz (GHz) range, are produced by special vacuum tubes (called klystrons, magnetrons and Gunn diodes).
→They are used in radar systems used in aircraft navigation, due to their short wave lengths.
→Radar also provides the basis for the speed guns used to time fast balls, tennis serves and automobiles.
→Microwave ovens are an interesting domestic application of these waves. In such ovens, the frequency of the microwaves is selected to match the resonant frequency of water molecules so that energy from the waves is transferred efficiently to the kinetic energy of the molecules.
→This raises the temperature of any food containing water.
→They are used in radar systems used in aircraft navigation, due to their short wave lengths.
→Radar also provides the basis for the speed guns used to time fast balls, tennis serves and automobiles.
→Microwave ovens are an interesting domestic application of these waves. In such ovens, the frequency of the microwaves is selected to match the resonant frequency of water molecules so that energy from the waves is transferred efficiently to the kinetic energy of the molecules.
→This raises the temperature of any food containing water.
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