TE26% 10:55 AM 27. Find the direction of the force acting on the pin, = ? 28. A figure skater started his spinning at 3 rev/sec initially with rotational inertia 38 kgm2. Then he pulled his arms closer toward the center of his body to decrease the moment of inertia to 22 kgm2. What is the final spinning in rev/sec? An Aluminum cable of length 3.5 m has 15,000N tensile force acting on it, if the wire is only allowed to be stretched by 1 mm before it breaks, 29. what must be the radius of the wire if the Young's modulus of Al is 6.9 x 1010 N/m2 ? 30. what is its tensile stress at this point? Three people are balanced on a uniform seesaw which has a weight of 150 N as shown in the figure. A m=7 7okg (2,0) (3, o) J-2,0) (54,0) W(l5ON) 31. find the mass of person B 32. find the normal force acting on the fulcrum.

TE26% 10:55 AM 27. Find the direction of the force acting on the pin, = ? 28. A figure skater started his spinning at 3 rev/sec initially with rotational inertia 38 kgm2. Then he pulled his arms closer toward the center of his body to decrease the moment of inertia to 22 kgm2. What is the final spinning in rev/sec? An Aluminum cable of length 3.5 m has 15,000N tensile force acting on it, if the wire is only allowed to be stretched by 1 mm before it breaks, 29. what must be the radius of the wire if the Young's modulus of Al is 6.9 x 1010 N/m2 ? 30. what is its tensile stress at this point? Three people are balanced on a uniform seesaw which has a weight of 150 N as shown in the figure. A m=7 7okg (2,0) (3, o) J-2,0) (54,0) W(l5ON) 31. find the mass of person B 32. find the normal force acting on the fulcrum.

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter10: Rotational Motion

Section: Chapter Questions

Problem 50P: A disk with moment of inertia I1 rotates about a frictionless, vertical axle with angular speed i. A...

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