Question

O v oE 11AP1 My et A Ye Teeche Native people throughout North and South America used a bola to hunt for birds and animals. A bola can consist of three stones, each with mass m, at the ends of three light cords, each with length t. The other ends of the cords are tied together to form a Y. The hunter holds one stone and swings the other two stones above his head (see Figure a). Both these stones move together in a horizontal circle of radius 2f with speed va- At a moment when the horizontal component of their velocity is directed toward the quarry, the hunter releases the stone in his hand. As the bola flies through the air, the cords quickly take a stable arrangement with constant 120-degree angles between them (see figure B). In the vertical direction, the bola is in free fall. Gravitational forces exerted by the Earth make the junction of the cords move with the downward acceleration . You may ignore the vertical motion as you proceed to describe the horizontal motion of the bola. (Use the following as necessary: m, v and t.) (a) Calculate the magnitude of the momentum of the bola at the moment of release. p (b) Calculate the horizontal speed of the center of mass of the bola after its release. v (c) Calculate the angular momentum of the bola about its center of mass after its release. L= (d) Calculate the angular speed of the bola about its center of mass after it has settled into its Y shape (e) Calculate the kinetic energy of the bola at the instant of release. K= (f) Calculate the kinetic energy of the bola in its stable Y shape K= (g) Explain how the conservation laws apply to the bola as its configuration changes. Robert Beichner suggested the idea for this problem. This anee heet e rw Need Help? t

Answer 1

Here we apply definition of linear momentum and angular momentum. Also apply law of conservation of angular momentum.

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