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I'm stuck on these questions based on inclined planes and pulley systems z.z
I'm ok with question 1 on impulses and change in momentum, but the rest is just gwaah.
Help would be appreciated
Since the left mass is accelerating at 2.8 m/s^2, the right mass is accelerating at -2.8 m/s^2.
MA = Fg - Ft... but A is negative, so flip Ft and Fg. Ft - Fg = MA. You know Ft now, Fg is 9.8*M. You need to use algebra to isolate the M. A is 2.8.
M(A + 9.8) = Ft. Ft is 3.5, so M = .27777, which is 5/18 kg.