Question 4. [10/50] About conservation of angular momentum Dumbbell Dumbbell -Professor (not a dumbbell) W2 A...

Transcribed Image Text:

Question 4. [10/50] About conservation of angular momentum Dumbbell Dumbbell -Professor (not a dumbbell) W2 A physics professor stands at the center of a frictionless turntable with arms outstretched and a 5.0kg dumbbell in each hand as in FIGURE-4. He is set rotating about the vertical axis, making one revolution in 2.0s. His moment of inertia (without the dumbbells) is 3.0 kg m with arms outstretched and 2.2 kg. m with his hands at his stomach. The dumbbells are 1.0m from the axis initially and 0.20m at the end. Please find his final angular velocity if he pulls the dumbbells inward to his stomach. BEFORE AFTER FIGURE-4 Conservation of angular momentum. Hint: No external torques act about the z-axis, so L, is constant. Thus, use the conservation of angular momentum: T-Z=0||=| T5 | 1,100% = 100;q= Here subindices i and f correspond to initial and final cases (or 1 and 2 cases), respectively. For this system, the moment of inertia is: I = Iprof+Idumbbells where dumbbells = mdumbbells "dumbbells Please do not forget to take dumbbells twice. Answer 4. Question 4. [10/50] About conservation of angular momentum Dumbbell Dumbbell -Professor (not a dumbbell) W2 A physics professor stands at the center of a frictionless turntable with arms outstretched and a 5.0kg dumbbell in each hand as in FIGURE-4. He is set rotating about the vertical axis, making one revolution in 2.0s. His moment of inertia (without the dumbbells) is 3.0 kg m with arms outstretched and 2.2 kg. m with his hands at his stomach. The dumbbells are 1.0m from the axis initially and 0.20m at the end. Please find his final angular velocity if he pulls the dumbbells inward to his stomach. BEFORE AFTER FIGURE-4 Conservation of angular momentum. Hint: No external torques act about the z-axis, so L, is constant. Thus, use the conservation of angular momentum: T-Z=0||=| T5 | 1,100% = 100;q= Here subindices i and f correspond to initial and final cases (or 1 and 2 cases), respectively. For this system, the moment of inertia is: I = Iprof+Idumbbells where dumbbells = mdumbbells "dumbbells Please do not forget to take dumbbells twice. Answer 4.