Problem 8: Penny is adjusting the position of a stand up piano of mass m, = 220 kg in her living room. The piano is l, = 1.35 m in length. The piano is currently at an angle of 0, = 33 degrees to the wall. Penny wants to rotate the piano across the carpeted floor so that it is flat up against the wall. To move the piano, Penny pushes on it at the point furthest from the wall. This piano does not have wheels, so you can assume that the friction between the piano and the rug acts at the center of mass of the piano. 0, Randomized Variables m, = 220 kg = 1.35 m Op = 33 degrees Part (a) Write an expression for the minimum magnitude of the force F, in N Penny needs to exert on the piano to get it moving. Assume the corner of the piano on the wall doesn't slide and the static friction between the rug and the piano is µg. Expression: Fs,min = Select from the variables below to write your expression. Note that all variables may not be required. a, B, us, 0, a, d, g, h, j, k, mp, n, P, S, t Part (b) The coefficient of kinetic friction between the carpet and the piano is u = 0.27. Once the piano starts moving, calculate the torque t, in N m that Penny needs to apply to keep moving the piano at a constant angular velocity. Numeric : Anumeric value is expected and not an expression. Part (c) Calculate the amount of work W, in J Penny does on the piano as she rotates it. Numeric : A numeric value is expected and not an expression. WD

Problem 8: Penny is adjusting the position of a stand up piano of mass m, = 220 kg in her living room. The piano is l, = 1.35 m in length. The piano is currently at an angle of 0, = 33 degrees to the wall. Penny wants to rotate the piano across the carpeted floor so that it is flat up against the wall. To move the piano, Penny pushes on it at the point furthest from the wall. This piano does not have wheels, so you can assume that the friction between the piano and the rug acts at the center of mass of the piano. 0, Randomized Variables m, = 220 kg = 1.35 m Op = 33 degrees Part (a) Write an expression for the minimum magnitude of the force F, in N Penny needs to exert on the piano to get it moving. Assume the corner of the piano on the wall doesn't slide and the static friction between the rug and the piano is µg. Expression: Fs,min = Select from the variables below to write your expression. Note that all variables may not be required. a, B, us, 0, a, d, g, h, j, k, mp, n, P, S, t Part (b) The coefficient of kinetic friction between the carpet and the piano is u = 0.27. Once the piano starts moving, calculate the torque t, in N m that Penny needs to apply to keep moving the piano at a constant angular velocity. Numeric : Anumeric value is expected and not an expression. Part (c) Calculate the amount of work W, in J Penny does on the piano as she rotates it. Numeric : A numeric value is expected and not an expression. WD