Question

Questions 9-12: A string is wrapped several times around the rim of a small hoop with radius R=0.1 m and mass 3kg. The free end of the string is held in place and the hoop is released from rest (see figure below). After the hoop has descended 2 m, (points) 9) The acceleration of the hoop as it descends 2 m 10) The moment of Inertia of the hoop is 11) The angular speed of the rotating hoop 12) The speed of center is Questions 13-15: At t=0 the current to a de electric motor is reversed, resulting in an angular un bu ACO (27 rad/st-(1 rad/sy (10 points)

Answer 1

Radius of hoop R=o.im ма кq ko'p мг 3% height descend h = am as using conservation of enersy Ei = Ef . . h = 2m Dowf dvf Keitkriti --T20 Vf. Rw 1. Ktf + Kxf tugf krizo krizo, ogit mgh mgha mvg ² + 1 I wf? mgh= £ my path (her) (444) 2 migh = 2 mVf? + £mvf? a mufa Vf = Igh = √9.8x2 = 4.43m/s 4.43 = 44.3rad /s as at vzur a) The acceleration b) . c) & a 4:43)*_024.9063 m/s2 2.X2 [a= 4.9063 m/s I- MRX = 3x10.02 -0.03 kg-ma Angular speed we V = 44-3 rad's The speed of center in Vcm= RW = 0.18 4413 (Vom = 4:43 m/s