Question C4. Assume you are designing a rubber mat with some frictional characteristics for a crate to be stable under an impact by an object. Such a scenario is demonstrated in Fig. 8, in which, a uniform sphere of mass m of 10.55 kg and radius r rolls without slipping toward a large crate with mass M = 95.25 kg that rests on top of a rubber mat nailed into the ground. The static coefficient of friction between the crate and the mat, Hs = 0.75. A spring with stiffness k is attached to the crate at a height h = 0.85 m above the mat, and the crate's mass centre G is located a distance d = 550 mm from either of its supports A and B. The sphere makes contact with the spring with a speed of v= 20 km/h. Determine (a) the spring constant k so that the crate just barely tips without slipping, and (b) explain the possible change in the parameters (i.e. increase of decrease of values) that may cause the crate to tip forward. d d m M win k g A Fig. 8 (C4)

Question C4. Assume you are designing a rubber mat with some frictional characteristics for a crate to be stable under an impact by an object. Such a scenario is demonstrated in Fig. 8, in which, a uniform sphere of mass m of 10.55 kg and radius r rolls without slipping toward a large crate with mass M = 95.25 kg that rests on top of a rubber mat nailed into the ground. The static coefficient of friction between the crate and the mat, Hs = 0.75. A spring with stiffness k is attached to the crate at a height h = 0.85 m above the mat, and the crate's mass centre G is located a distance d = 550 mm from either of its supports A and B. The sphere makes contact with the spring with a speed of v= 20 km/h. Determine (a) the spring constant k so that the crate just barely tips without slipping, and (b) explain the possible change in the parameters (i.e. increase of decrease of values) that may cause the crate to tip forward. d d m M win k g A Fig. 8 (C4)

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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