Nitrogen is essential for plants and animal life as it is a constituent of major biomolecules like proteins and nucleic acids. It is available in plenty in the atmosphere. However, for plants to be able to use it efficiently, it has to be converted into some nitrogenous compounds. This conversion is called nitrogen fixation. Nitrogen in the combined form is also necessary for the manufacture of explosives and chemical fertilizers.
In nature, nitrogen is fixed by some microorganisms and by lightning. The nitrogen fixing bacteria living in the root of leguminous plants and some blue-green algae convert nitrogen gas into ammonium compounds, which are then absorbed by plants. The plants supply the bacteria with food, which in turn secrete ammonium compounds that are absorbed and used by the plants.
Lightning causes atmospheric nitrogen to combine with oxygen of the air to form nitrogen oxides. These oxides then combine with moisture in the air and are carried down by rain as nitrates, which are taken up by plants. The plants supply the bacteria with food, which in turn secrete ammonium compounds that are absorbed and used by the plants. For plants to be able to use it efficiently, it has to be converted into some nitrogenous compounds.

A geomagnetic storm is a short term perturbance of earth’s magnetosphere caused by interruption in space weather. In other words, it is a phenomenon caused by disturbances in the earth’s magnetic field. It gives rise to spurious currents in submarine cables and interferes with radio communication. This geomagnetic storm which will be caused by solar wind shock wave which in particular strikes the earth’s magnetic field from 24 to 36 hours after the event associated with solar coronal mass ejection, coronal holes or by solar flares. This will usually happen when shock wave travels in direction of earth. The magnetosphere’s solar wind pressure will increase or reduce based on the sun’s activity. The disturbance in earth’s magnetic field is caused by the sudden short-lived brightening of the sun’s surface called solar flare. A continuous flow of charged particles emanating from the sun reaches earth. On striking earth some of these are captured by the earth’s magnetic field causing disturbance in it. Magnetic storms cause disturbance in the uppermost region of earth’s atmosphere thus interfering with radio communication. Magnetic storms are accompanied by emission of intense and colorful lights called ‘auroras’ seen in the polar regions during winters. Magnetic storms will occur for 24 to 28 hours, else some will for many days.

MRI or the Magnetic Resonance Imaging is a technique for obtaining images of organs for medical diagnosis without having to resort to surgery. The technique uses the phenomenon of Nuclear Magnetic Resonance (NMR). MRI provides more difference in soft tissues in body than CT and most useful in neurological, musculoskeletal, cardiovascular and oenological imaging. Through MRI it is possible to differentiate between the various types of soft tissues. This gives it an edge over X-ray photography. For obtaining the images, the property of certain substances which selectively absorb energy when irradiated by electro-magnetic radiation is used. The nuclei of certain atoms behave like tiny magnets. When substances with such atoms are placed in a magnetic field and continuously irradiated by electro-magnetic waves of varying frequency, there comes a frequency called resonance frequency when a part of the electro-magnetic energy is absorbed by the substances. The value of the resonance frequency is proportional to the intensity of the applied magnetic field and the nature of the substance that exhibits nuclear magnetism. When pressure is released, they again turn into gaseous forms as happens when the valve in the gas is released. LPG is volatile and highly inflammable and hence needs extra care while using.