weird hexagons and green thm
Hi, I would appreciate if someone could help. thanks.
Calculate the work done by the non conservattive force F=x³j in moving a particle,around the regular hexagon with vertices at (√3,1),(0,2),(-√3,1),(-√3,-1),(0,-2) and (√3,-1) in that order. (use greens theorem).
For this question I tried to use symmetry : I sketched the hexagon out then,I divided into half.
and the formula m(gradient)=(y2-y1)/(x2-x1)
Please see diagram attached : Attachment 28760
y=(x²+2x√3+6)/3For c2:y=2+(x/√3);For c3:y=1
I am really not sure what I am doing wrong . could someone please check. obviously if its a positive gradient ,need pos sign for neg gradient slanting the other way I need a negative sign . is there anything else I have to account for ?cuz I seem to be somethimes getting wrong answers off by minus 1.
Re: weird hexagons and green thm
I'm not sure what you are doing! In particular, I have no idea why you are looking at the individual sides of the hexagon. You were told to do this using "Green's theorem" which says that the integral of a vector function, , around a closed path, counterclockwise, is equal to the integral of over the region bounded by the closed path.
Here the vector function given is so that f(x,y)= 0 and [/tex]g(x,y)= x^3[/tex] so you want to integrate over the hexagon. Since that is symmetric about the y- axis, it is sufficient to integrate of x= 0 to and double. The lower boundary is the line from (0, -2) to . The slope of that line is and the equation is . Similarly, the upper boundary is the line from (0, 2) to . The slope of that line is and the equation is .
So the solution is .