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प्रश्न
Why are microwaves considered suitable for radar systems used in aircraft navigation?
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उत्तर
Microwaves are considered suitable for radar systems used in aircraft navigation because they have a short wavelength range (10−3 m–0.3 m), which makes them suitable for long-distance communication.
संबंधित प्रश्न
To which part of the electromagnetic spectrum does a wave of frequency 5 × 1011 Hz belong?
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Continuous X-rays are made to strike a tissue paper soaked with polluted water. The incoming X-rays excite the atoms of the sample by knocking out the electrons from the inner shells. Characteristic X-rays are analysed and the intensity is plotted against the wavelength. Assuming that only Kα intensities are detected, list the elements present in the sample from the plot. Use Moseley's equation v − (25 × 1014Hz)(Z − 1)2.
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Name the part of the electromagnetic spectrum which is:
Suitable for radar systems used in aircraft navigation.
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Microwaves are electromagnetic waves with frequency in the range of.
The ratio of contributions made by the electric field and magnetic field components to the intensity of an EM wave is ______.
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In an atom X, electrons absorb the energy from an external source. This energy “excites” the electrons from a lower-energy level to a higher-energy level around the nucleus of the atom. When electrons return to the ground state, they emit photons.
The figure below is the energy level diagram of atom X with three energy levels, E1 = 0.00eV, E2 = 1.78eV and E3 = 2.95eV. The ground state is considered 0 eV for reference. The transition of electrons takes place between levels E1 and E2.
- What wavelength of radiation is needed to excite the atom to energy level E2 from E1?
- Suppose the external source has a power of 100 W. What would be the rate of photon emission?
