A wind farm generator uses a two-bladed propeller (see figure) mounted on a pylon at a height of 20 m.
The length of each propeller blade is 12 m. A small piece from the tip of the propeller breaks off when the propeller is vertical. At that instant, the period of the motion of the propeller is 1.2 s. The fragment flies off horizontally, falls with negligible air resistance, and strikes the ground at P.
(a) How far is point P from the base of the pylon?
(b) At what angle with respect to the vertical is the fragment moving just as it strikes the ground at P?
What will be an ideal response?
Question 2
A disk-shaped space station 175 m in diameter spins uniformly about an axis perpendicular to the plane of the disk through its center. How many rpm (rev/min) must this disk make so that the acceleration of all points on its rim is g/2?
What will be an ideal response?
A mounted police officer in Poland
Normal development of posture and spinal curves. (A) Toddler: Protruding abdomen; lumbar lordosis. (
Due to compressibility, atmospheric mass gradually “thins out” with height.
Human Figure
Wind energy
The Farm-to-Table Continuum