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Engineering 25. Tutorial: Flat Friction. Bruce Mayer, PE Licensed Electrical & Mechanical Engineer BMayer@ChabotCollege.edu. Spring-n- Wts on Ramp.
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Engineering 25 Tutorial: FlatFriction Bruce Mayer, PE Licensed Electrical & Mechanical EngineerBMayer@ChabotCollege.edu
Spring-n-Wts on Ramp • Two blocks A and B have a weight of 10 lb and 6 lb, respectively. They are resting on the incline for which the coefficients of static friction are µA = 15% and µB = 25%. Determine the incline angle for which both blocks begin to slide. Also find the required stretch or compression in the connecting spring for this to occur. The spring has a stiffness of k = 2 lb/ft.
Conceptual Analysis • Since Block-A has the lower µS value, it will Slide FIRST, thereby PULLING Block-B Down the ramp with it • Thus expect the Dual-Block Slip-Angle • Take the FBD of both Blocks noting that the Spring Force, FS, will be equal & opposite for both blocks