FORMULAE

1. Radius of Sump Dome   =  R  =   {b² + 4r² }/{8r} 
     where
      b = Diameter of Sump
      r = rise of sump dome

2. Staircase Footing VRCC Calculation:
     1. Flat Portion                     -  L x B x d
     2. Trapezoidal Portion         -  use formulae 1 or 2  as below 
          

                       a2
               +---------------+
            b2/               / \---------
             +---------------+   \      |
            /                |    \     |
           /.................|.... +    | h
          /                  |    /     |
         /                   |   /      |
        /                    |  /b1 ------
       /                     | /
      /                      |/
     +-----------------------+
                a1

     V = [a1*b1 + a2*b2 + (a1*b2 + a2*b1)/2] * h/3

Here the bottom is a1 x b1, and the top is a2 x b2, with the a's 
parallel and the b's parallel (this is important).

An alternative version of the formula, using the average length and 
width, is:

     V = [a1*b1 + a2*b2 + 4((a1+a2)/2 * (b1+b2)/2)] * h/6
          \___/   \___/     \___________________/
        area of  area of          area of
         bottom    top             middle
       rectangle rectangle       rectangle

The "middle" rectangle has sides that are the average of the sides of 
the top and bottom rectangles:

                       a2
               +---------------+
            b2/               / \---------
             +---------------+   +      |
            /                |  / \     |
           /.................|./.. +    | h
          /                  |/   /     |
         +-------------------+   /      |
        /      (a1+a2)/2     |  /b1 ------
       /                     | /
      /                      |/
     +-----------------------+
                a1

HOW TO KNOW ANGLES

The formula for calculating the sum of the interior angles of a regular polygon is: (n - 2) × 180° 



where n is the number of sides of the polygon. This formula comes from dividing the polygon up into triangles using full diagonals. We already know that the interior angles of a triangle add up to 180° 





ex:- three sides    - Triangle  : (3-2)*180 = 180°             ---> each internal angle = 180/3     = 60°

        Four sides    - Square     : (4-2)*180 = 360°             ---> each internal angle = 360/4     = 90°

        Five Sides    - Pentagon : (5-2)*180 = 540°             ---> each internal angle = 540/5     = 108°

        Six Sides      - Hexagon  : (6-2)*180 = 720°             ---> each internal angle = 720/6     = 120°

        Seven Sides - Heptagon : (7-2)*180 = 900°            ---> each internal angle = 900/7     = 128.57°

        Eight Sides   - Octagon   : (8-2)*180 = 1080°           ---> each internal angle = 1080/8   = 135°

        Nine Sides    - Nonagon  : (9-2)*180 = 1260°           ---> each internal angle = 1260/9   = 140°

        Ten Sides     - Decagon   : (10-2)*180 = 1440°         ---> each internal angle = 1440/10 = 144°






CONVERSION FACTORS



Yield of Borewell_Coversion from inch to GPH(Gallons per Hour) 


LENGTHS:


1 Mile       =   1.609344 Kms


1 Mile       =   1609 Mts


1 Mile       =   8 Furlongs


1 Km        =   1000 Mts

1 Km        =   4.97 Furlongs

1 Furlong  =  0.201 Kms

1 Furlong  =  220 Yards


1 Metre     =  1.094 Yards


1 Metre     =  3.28084 foot


1 Yard       =  3 Feets

1 Foot       =  0.3048 Metre

1 foot        =   12 inches

1 inch        =   2.54 cms  or 25.40 mm

1 Cm         =  0.393701 inch


AREA:


1 Acre       =   40 Gunta's


1 Gunta     =  121 Sq Yards


1 Acre       =  4840 Sq Yards


1 Gunta     =  101.17 Sq Mts


1 Gunta     =  1089 Sq Ft  (33 x 33 Sft)

1 Hectare  =  2.47105 Acres


1 Hectare  =  10000 Sq Mts  (100x100 Sq Mts)

1 Sq Km    =  247.10 Acres


1 Sq Mt     =   1.20 Sq Yards


1 Sq Yard  =  9 Sq Ft


1 Cent        =  48.40 Sq Yards


CUBIC MEASURES:


1 M. Tonne = 1000 Kgs


1 Quintal     = 100 Kgs

1 KL           =  1000 Lits of water


1 Litre         =  1000 Ml of water


1 Cum         =  35.3147 Cft


1 Cum         = 1000 Litres of water





OTHERS


1 Gallon    =  4.54609 Litres     (Imperial Gallon or UK Gallon)


1 TMC      = 1 thousand million cubic feet

                  =  1000 x1000000 x cft

                  = 1000 x 1000000 x (0.3048)3 Cum


                  = 28316846.59 Cum

                  = 28316846592  Litres of water

                  = 6228835459  Gallons of water


1 MGD     = 1 Million Gallons per day

                  = 1000000 gallons per day


                  = 1000000 x 4.54609 lits per day

                  = 4546090 x 24 lits per hour

                  = 109106160 x 60 x 60 Lits per sec


                  = 392782176000 lits per sec

1 Cusec     = 7.48 Gallons       (Cusec - Cubic feet per sec )  

1 Cusec     = 34.00 Lits