A Wind Farm Generator Uses a Two-Bladed Propeller Mounted on a Pylon

question 123

Multiple Choice

A wind farm generator uses a two-bladed propeller mounted on a pylon at a height of 20 m, as shown in the figure. The width of the pylon is very narrow, and the length of each propeller blade is 12 m. A tip of the propeller breaks off just when the propeller is vertical. The fragment flies off horizontally, falls, and strikes the ground at point P with negligible air resistance. Just before the fragment broke off, the propeller was turning uniformly, taking 1.2 s for each rotation. How far is point P from the base of the pylon?

• A) 120 m
• B) 130 m
• C) 140 m
• D) 150 m
• E) 160 m