Two logs of radius 80 cm and 20 cm have a single wire around them as shown in the figure below. Find the length of the wire. Hint: ∠ACD and ∠BDC are right angles. Draw a linethrough B parallel to CD meeting AC at E. Homework Help ✎
Label the drawing!
Line AB = 100 because it is the sum of the radii of both logs.
Then cosθ = 0.6, so θ ≈ 0.927 radians. Thus the wire length around the large log is 80(2π– 2(0.927)) = 354.287 cm.