已知锥形圆筒的上圆直径d2=230下圆直径d1=238高度h=114请问展开图怎样画?怎样计算?
展开图的大圆弧半径为R1,小圆弧半径为R2,弧所对的圆心角为A.
R1-R2=(h^2+((d1-d2)/2)^2)^0.5=(114^2+((238-230)/2)^2)^0.5=114.280357
A=(d1*PI)/R1=(d2*PI)/R2
d1/R1=d2/R2
R2=(d2/d1)*R1=(230/238)*R1
R1-R2=R1-(230/238)*R1=114.280357
R1*(8/238)=114.280357
R1=114.280357*(238/8)=3399.84
R2=(230/238)*R1=(230/238)*3399.84=3285.56
A=(d1*PI)/R1=(238*PI)/3399.84=0.219922弧度=0.219922*180/PI=12.6度