GEOGRAPHY PRACTICAL GRADUATION ( CARTOGRAM)

  •PROPORTIONAL CIRCLE•
DEFINITION:- Circular diagram are two dimensional consisting of a series of circles proportional in size to the quantities they represents. Depending on the nature of data,circular diagram may be constructed in two ways :-
(i) Simple Circular Diagram.
(ii) Compound Circular Diagram.
It is called proportional circle because the size of the circles increase or decrease of the quantity representivelly.

PRINCIPAL:- The construction of circular diagram is based on the principal that the area of the circle (a) representable item (i) is directly proportional to quantity of item (q) to be down empirically.

METHOD :- The radius of the the circles can be computed by considering the respective area or population as πr2=x 
Or r=√x/π
(x= area/population to be represented. Here r is the various lengths worked out will be converted into 'cm' or inches according to the scale chosen.

 USE :- Circles representing area or population being proportional in diameter in terms of the amount of area of figure of population they represents.

DEMERITS :- Total population or areas are represented by the circle diagram but the division of the total population or total area [ such as male - female, rural Urban ] cannot be represent by this diagram.