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The pilot of an airplane executes a vertical loop which in part follows the path of a “four-leaved rose,” r = (–600 cos 2θ) ft, where θ is in radians. If his speed is a constant vP = 80 ft/s, determine the vertical reaction the seat of the plane exerts on the pilot when the plane is at A. He weights 130 lb. Hint: To determine the time derivatives necessary to compute the acceleration components ar and a0, take the first and second time derivatives of r = 400(1 + cos θ). Then, for further information, use Eq. 12-26 to determine
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Engineering Mechanics: Statics & Dynamics (14th Edition)
- A bob of a 2-m pendulum describes an arc of circle in a vertical plane. If the tension in the cord is 2.5 times the weight of the bob for the position shown, find the velocity and acceleration of the bob at that position. 8. 2 m 30° m.arrow_forwardThe x- and y-motions of guides A and B with right-angle slots control the curvilinear motion of the connecting pin P, which slides in both slots. For a short interval, the motions are governed by x = 12 +0.55t² and y = 16-0.57t³, where x and y are in millimeters and tis in seconds. Calculate the magnitudes of the velocity v and acceleration a of the pin for t = 2.5 s. Sketch the direction of the path and indicate its curvature for this instant. B P Part 1 Calculate the x- and y-components of the velocity. Answers: Vx= mm/s Vy= mm/s iarrow_forwardIn an archery test, the acceleration of the arrow decreases linearly with distances from its initial value of 14500 ft/sec² at A upon release to zero at B after a travel of 33.0 in. Calculate the maximum velocity v of the arrow. Answer: v= i BI 33.0" ft/secarrow_forward
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