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48)Revealed: What to expect on Republic Day 2021and what not to

India Republic Day -- Republic Day 2021: In 2020it was the agitation against the Citizenship Amendment Act (CAA). Nowthousands of farmersmainly from Punjab and Haryanahave been camping at the sides of Delhi for more than a couple of monthsdemanding the Centre repeal the three farm laws. To the second year in a stripRepublic Day celebrations from the national capital will be placed under the shadow of raging protests against laws transferred by the Centre. In 2020it was the agitation against the Citizenship Amendment Act (CAA). This timethousands of farmersmainly from Punjab and Haryanahave been camping at the sides of Delhi for more than a couple of monthsdemanding the Centre repeal the three farm laws. This specific years Republic Day ornement will also be the first major general public event in pandemic moments. What is new this year The presentation will be pared down the number of spectatorsthe size of walking in line contingents and other side sights. The spectator size has bee...
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Newtonian mechanics

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Perhaps surprisingly, molecular vibrations can be treated using Newtonian mechanics to calculate the correct vibration frequencies. The basic assumption is that each vibration can be treated as though it corresponds to a spring. In the harmonic approximation the spring obeys Hooke's law: the force required to extend the spring is proportional to the extension. The proportionality constant is known as a force constant, k . The anharmonic oscillator is considered elsewhere. F o r c e = − k Q {\displaystyle \mathrm {Force} =-kQ\!} By Newton's second law of motion this force is also equal to a reduced mass, μ , times acceleration. F o r c e = μ d 2 Q d t 2 {\displaystyle \mathrm {Force} =\mu {\frac {d^{2}Q}{dt^{2}}}} Since this is one and the same force the ordinary differential equation follows. μ d 2 Q d t 2 + k Q = 0 {\displaystyle \mu {\frac {d^{2}Q}{dt^{2}}}+kQ=0} The solution to this e...
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Number of vibrational modes

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For a molecule with N atoms, the positions of all N nuclei depend on a total of 3 N coordinates, so that the molecule has 3 N degrees of freedom including translation, rotation and vibration. Translation corresponds to movement of the center of mass whose position can be described by 3 cartesian coordinates. A nonlinear molecule can rotate about any of three mutually perpendicular axes and therefore has 3 rotational degrees of freedom. For a linear molecule, rotation about the molecular axis does not involve movement of any atomic nucleus, so there are only 2 rotational degrees of freedom which can vary the atomic coordinates. An equivalent argument is that the rotation of a linear molecule changes the direction of the molecular axis in space, which can be described by 2 coordinates corresponding to latitude and longitude. For a nonlinear molecule, the direction of one axis is described by these two coordinates, and the orientation of the molecule about this axis provides a third r...
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