Question

弓形,弓高0.78,半径1.3,求弧长.

Answer 1

弓高H=0.78,半径R=1.3,求弧长C?

弧所对的圆心角为A.

A=2*ARC COS((R-H)/R)

=2*ARC COS((1.3-0.78)/1.3)

=132.84度

=132.84*PI/180

=2.318559弧度

C=R*A=1.3*2.318559=3.014