OV cobra.parkland.edu C 828 PHY121_HWS - PHY-... PHY121_ICPS - PHY-. Dropbox Folders - P. Don't Mess With My. C Cobra.parkland.edu.. *Course Hero MYour question was a... C See-saw ( 4.08 M En. + Table of Contents > HWs & ICPs > PHY121_HWs PHY121 HWs ~ Q T V 57 of 89 -|+ Automatic Zoom [ > > HW13 PHY121 1) A record (R = 0.0889 m ) is spun CW by a turntable. By placing your finger on the record, you can create a 14.0 N friction force on the record. What is the torque you put on the record if you place your finger: Answers: a) on the eastern edge of the record? [N-m] +1.24 or 1.24 CCW b) on the western edge of the record? [N-m] +1.24 or 1.24 CCW c) 0.0193 m south of the center of the record? [N-m] +0.270 or 0.270 CCW d) 0.0500 m south of the northern edge of the record? [N-m] +0.545 or 0.545 CCW e) 0.0693 m, 33.8 . N of W from the center? [N-m] +0.970 or 0.970 CCW f) the dead center of the record (hypothetically, if the pin 10.00 wasn't in the way)? [N-m]i 0 l" Ecobra.parkland.edu Cl m m 3) One of a raoecafs wheels (m = 17.1 kg, R = 0.206 m, In = 1/z m R2) is initially at rest, when the driver performs a burnout. This causes the wheels to spin much too fast for rolling, and creates a constant kinetic friction force of 580. N. When the wheel gets to angular speed of 65.9 rad/s, it has moved forward 2.84 m and rotated 22.6 rad. If the racecar added a total of 2.23x10' J of work to the wheel during that time, then what is: Answers: a) the initial total energy of one Mieel? [J] 0.00 b) the linear work done by kinetic friction? [J] +1.65x10' It ADDS energy linearly! c) the rotational work done by kinetic friction? [J] -2.70x103 It takes away energy rotationally d) the nal rotational energy of one wheel? [J] 788. e) the nal linear kinetic energy of one wheel? [J] 389. f) the nal linear speed of the wheel? [m/s] 6.75 3" Reflect in ePortfolio Q Download a Print E; Open with docReader AV Alternative formats Activity Details l; I V cobra.parkland.edu PHY121_HWS - PHY-... PHY121_ICPS - PHY-... Homepage - PHY-12.. Course Hero C Cobra.parkland.edu... M Your question was a... C See-saw ( 4.08 M En... Spotify - oldies + HW15 PHY121 1) A 33.6 kg ball with a 0.798 m radius is rolling on the ground with an angular velocity of 6.95 rad/s CCW when it hits a wall, then rolls the other way at 4.26 rad/s CW. If its Izz = 2/5 m R', then what is: Answers: a) the ball's initial rotational kinetic energy? [J] 207. b) the ball's final rotational kinetic energy? [J] 77.7 c) the ball's initial linear kinetic energy? [J] 517. d) the ball's final linear kinetic energy? [J] 194. e) the ball's initial total energy? [J] 723. f) the ball's final total energy? [J] 272. g) the total amount of work done on the ball? [J] -452. :Reflect in ePortfolio Download Print Open with docReader A Alternative formats