Question 7.5 An inextensible thread wraps around the axle of a yoyo. The radius of the axle is r and the radius of the yoyo is R. Denote by M the mass of the yolo. The coefficient of static friction between the yoyo and the ground is μ. Suppose that the string is pulled under the tension T an angle from the horizontal. (a) Find an angle 0 such that there is zero net torque acting on the yoyo. (b) Using that angle 0, show that the maximum tension Tmax that can be applied until the yoyo moves is Tmax = μMg cos +μsin R T μ (7.5.1)

Question 7.5 An inextensible thread wraps around the axle of a yoyo. The radius of the axle is r and the radius of the yoyo is R. Denote by M the mass of the yolo. The coefficient of static friction between the yoyo and the ground is μ. Suppose that the string is pulled under the tension T an angle from the horizontal. (a) Find an angle 0 such that there is zero net torque acting on the yoyo. (b) Using that angle 0, show that the maximum tension Tmax that can be applied until the yoyo moves is Tmax = μMg cos +μsin R T μ (7.5.1)

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.57P: The square-threaded screw with a pitch of 10 mm and a mean radius of 18 mm drives a gear that has a...

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