How do I find the diameter of a circle equal to 10m squared?

I need to survey individual blocks of land at 10 x 10 m (100 square meters).





Instead of marking the square out using 4 marker points I would like to measure this on the ground with a single stick and rope (to save time).





I want to place the stick in the ground, unravel the rope and walk in a circle from start to finish. How long does my rope need to be?

How do I find the diameter of a circle equal to 10m squared?
Well the area of a circle is Pi * r^2








So 100 = Pi x r^2





So 100/Pi = r^2





So Sqrt(100/Pi) = r





r = the length of rope you need (it's the radius not the diameter)





I make that 5.64 metres
Reply:It appears that you are required to survey parcels of land which are SQUARE, the sides of which are 10m long i.e. covering an area of 100sq.m.





How does marking out a circle who's area is 100sq.m. help you to do that?


When I calculate the radius of a circle with an area of 100sq.m. I get 5.64m, i.e. a diameter of 11.28m.


This circle is larger than the sides of the square but smaller than the diagonals of the square!!
Reply:area of circle=pi *(d^2)/4


where d is the diameter of circle


pi=22/7


10=pi*(d^2)/4


d=root(10*4/pi)


d=3.56753034


you can measure it
Reply:a=pid^2/4





10=pid^2/4





d=sqrt(40/pi)=3.57
Reply:3.57
Reply:////////


a==pid^2/4


10=pid^2/4


d=sqrt(40/pi)=3.57