can someone help me solve this questions?
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(a): Newton's equation would have two components. To maintain the centripetal acceleration you need a tension in the string T = mv2/R. To counter the friction and maintain a constant speed, you need an external tangential force F = μkmg. 2. The external force supplies power = Fv. 3. Set T = (2 kg)g to support the weight of the lower mass. 4. Without the external force, the torque from friction would cause a decrease in the angular momentum, a decrease in the tension, a decrease in the radius, and allow the lower mass to accelerate downward. Starting from equilibrium, its downward velocity would start at zero and increase with time (in a complex fashion and ending at zero when the upper mass hits the hole). I set up a numeric simulation of this system using a fixed xy system with its origin at the hole. I let t = 0 when the external force was removed and Δt = 0.01 sec. The upper mass started at x = 0.5 m and y = 0 with an equilibrium vy of 2.556 m/s. It followed a spiral path in toward the origin completing one cycle at t = 1.09 sec., and crossing the x axis at 0.3 m with a speed of 1.95 m/s. The downward speed of the hanging mass increased slowly, reaching a maximum of 0.34 m/s just before the first half cycle and then decreased even more slowly after that.