Sol. a) Single phase,split-phase AC motor b) 6-pole No-load Speed 1200 rpm (Norton Table 2-6) Full-load Speed 1140 rpm 63000H T= n T= 63000H63000×0.75 1140 =41.4bin n c) Tsart =1.5Trated Ta=1.5Tad=1.5×41.4lb-in=62.2lb·in d)Threak =345%Trated T6reak=345%T,aed=345%×41.4=142.81b-in Problem 3: Three examples of motors,with their parameters are listed in the Table below.For each case pick the best motor. a)A rotary load with a moment of inertia of 0.02 Kg m2 is driven by a gear reducer. Select the motor that produces the minimum power dissipation and the motor that results in minimum temperature rise.Find the optimal gear ratio in either case. b)A mass of M=0.75 Kg must be driven by a pulley.Select the motor that can drive it under minimum temperature rise and find the optimal radius size.Sol. a) Single phase, split-phase AC motor b) 6-pole No-load Speed 1200 rpm (Norton Table 2-6) Full-load Speed 1140 rpm c) d) Tbreak  345%Trated Problem 3: Three examples of motors, with their parameters are listed in the Table below. For each case pick the best motor. a) A rotary load with a moment of inertia of 0.02 Kg m2 is driven by a gear reducer. Select the motor that produces the minimum power dissipation and the motor that results in minimum temperature rise. Find the optimal gear ratio in either case. b) A mass of M = 0.75 Kg must be driven by a pulley. Select the motor that can drive it under minimum temperature rise and find the optima1 radius size. 63000H T n  63000 63000 0.75 41.4 1140 H T lb in n      1.5 Tstart  Trated 1.5 1.5 41.4 62.2 Tstart Trated    lbin  lbin 345% 345% 41.4 142.8 Tbreak Trated     lbin