Question

6 5 o Mail - Catharine M 00 TEXT BOOK (1) B Mar 23, 2020 - KIN ® Homepage - Unive Crowdmark Quiz 10 long q ~ c Get Homework He + - E → 0 file:///C:/Users/Catha/OneDrive/Documents/Quiz%2010%20long%20question%20angular%20momentum%20(1).pdf 1 of 1 0 – + D Fit to page 9 Page view A Read aloud Add notes 6 H A child (mc = 25 kg) is spinning on the edge of a merry-go-round (Rm= 2 m, mm= 150 kg) at a constant angular velocity of 1 rev/s. The child slowly walks to the center of the merry-go-round. Treat the child as a point particle and the merry-go-round as a uniform solid disk. Neglect friction on the axle of the merry-go-round. a) What is the total initial moment of inertia, li, and angular momentum, L? (points) b) What is the final moment of inertia, If, and angular momentum, LA? (points) c) What is the final angular velocity of the merry-go-round? (Opoints) d) What are the total initial and final kinetic energy? Is kinetic energy conserved? If not, why not? (6 points) e) If instead of walking to the centre of the merry-go-round, the child jumped off in a radial direction, what would happen to the merry-go-round, justify your answer? (6points) 4:50 PM Type here to search o B e B ê 0 W ^ M . 1) - ENG 2020-03-27

Answer 1

- Mc = 25kg, R=2m, Mm = 150kg, wi= 1 MENIS - Here no external torque so angulor-momentum will be conserved (El) wi- { lf) wf (Ict lm) i Wiz (let Imf wf (MR+ MwR?) wrz (0 + MmR") wf [ 25805* + {ysore) |x 1 = ( 4x1904@), wf 400 x1 = 300x wf o final ang. I wf - 400 Velleity Hevis = 1.33 hev/s 300 Esime R² + 1 MMR² 400 lg-m? & If = 1 MMR² = 300 lcg-m2 / Liz Elixwi - 4008 1 X 2X = 2513,27 kg-m2 S f = { Ifxwf a 300 x 4 x 27 = 2513,27 kg-m2 This II, W -1 x 400x (22)- 7895,68 leg-mys2 . (P= I If Wf2 = 1x 300 x 24 x 24 ) ² 10527.57 Kg - 12/32 No. Kinetic En. Is not conserved. bloz child has done some - work in moving to centre and this work increased the KE ey I (MOI) will be decreased so angular speed will be increases (1 a/w) [ L-Iu ]