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LIFE OF PI IN SCIENCE

  


   Suppose a circle grows, along with it, its diameter also grows.  We can say, circumference of a circle is proportional to its diameter.
C proportional to 2r
There must be a number or constant which bridges the two.

 C = 3.14.....*2r
3.14....... = π = C/2r

 That number is 3.14..  and it is famously known as pi.
Why this particular number?  We have to ask the creator only.  This is a irrational or a never ending number.  A circle having circumference of 22 units will have the diameter of 7 units.  So sometimes pi is denoted by 22/7.  A circle having unit radius will have the circumference 2pi.

 That is,
       C = π*2r
       C = 2π      since  r= 1
   We know, a full circle( C ) is having a total angle of  360 degrees.
  Hence 2*π = C = 360 degrees.
     π = 180 degrees
     π/2 = 3.14/2 = 90 degrees
Hence we can measure any angle in terms of pi.  This unit is called Radian.

      In physics: circular motion , wave motion and oscillations appear every where.  All are similar.  So a π  represents a half a  circle or half a  wave or half a oscillation.  Consequently it pops up in many physics and mathematical formulas.

      Using powerful computers, we have calculated many digits in pi.  High accuracy of pi is needed for the calculations in astronomy and cosmology.  Pi can be applied to the orbits of electron in the atom or revolution of planets around the sun.

      The constant pi will always be a constant everywhere in the universe for eternity.  

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