My thoughts !! | எனது எண்ணங்கள் !!

This blog is to express my mind, thoughts and scrabbles. A place to express what I am!

Thursday, 30 April 2020

108 years old Elephant Gate bridge pulled down!






108 years old Elephant Gate Bridge has been pulled. For past few years traffic was stopped permanently on this bridge and supporting steel rods were erected to hold the bridge as it has gone old and rickety. Secondly, the bridge was 50 metres in length. Which created a chicken neck like situation. Where tracks get squeezed allowing only 6 tracks under it. Before and after the bridge tracks are broad. Resulting in unduly holdups. A train arrives on time or well ahead to perambur or basin bridge, but holdup for 20 to 30 minutes due to this bridge as only 6 trains - 3 up and 3 down can pass any given time. There by affecting the train movements to and fro from Central. Now railways will build a steel bridge of 150 metres, there by giving room to atleast 10 tracks and holdups will be reduced as trains can enter and exist easily. Plans also there to shift west bound trains to Salt Cotaurs as 4th terminal. 

Sunday, 26 April 2020

Is it Day or Night?



Why sky appears blue even in night? What are those two stars above that water tank?   Irrespective of day or night, our atmosphere scatters blue colour. This was found by Sir. Chandrasekhara Venkata Raman, FRS or Sir. C.V. Raman! He was the recipient of the Nobel Prize for Physics in 1930 for the discovery that when light traverses a transparent material, some of the light that is deflected changes in wavelength. This phenomenon is now called Raman scattering and is the result of the Raman effect.  Raman scattering or the Raman effect is the inelastic scattering of a photon. It was discovered by C. V. Raman and K. S. Krishnan in liquids, and by G. Landsberg and L. I. Mandelstam in crystals. The effect had been predicted theoretically by A. Smekal in 1923.  When photons are scattered from an atom or molecule, most photons are elastically scattered (Rayleigh scattering), such that the scattered photons have the same energy (frequency and wavelength) as the incident photons. However, a small fraction of the scattered photons (approximately 1 in 10 million) are scattered by an excitation, with the scattered photons having a frequency different from, and usually lower than, that of the incident photons. In a gas, Raman scattering can occur with a change in energy of a molecule due to a transition . Chemists are concerned primarily with such transitional Raman
 effect.  Those two stars are: binary star system Alpha Centauri AB / Rigil Kent ( 4.39 light years from sun) and Hader / Beta Centauri 525.21 Ly away) to its right is Southern Cross or Crux . above is Libra and to left is Scorpios and Lupus constellations.  If we draw a cross line from between these two stars and draw a line from Acrux or Alpha 1 Crux, both will point to south pole point! There is no specific star pointer for Earth's Southern pole as in North pole where we have Polaris!

Image Settings: F2.8, ISO 100. 30 sec exposure. Taken in 2013.  Camera: Fujifilm Hybrid DSLR.