{"id":15728,"date":"2022-05-18T18:53:21","date_gmt":"2022-05-18T18:53:21","guid":{"rendered":"https:\/\/alnojoumacademy.com\/?p=15728"},"modified":"2022-10-01T21:25:08","modified_gmt":"2022-10-01T21:25:08","slug":"rotational-motion","status":"publish","type":"post","link":"https:\/\/alnojoumacademy.com\/en\/rotational-motion\/","title":{"rendered":"rotational motion"},"content":{"rendered":"<h1 class=\"TopprQuestion_question__d2pZj utils_customScrollBar\" style=\"text-align: center;\">The figure shows three small spheres that rotate about a\u00a0vertical axis. The perpendicular distance between the axis and the center of each sphere is given. Rank the three spheres according to their rotational inertia about that axis, greatest first.<\/h1>\n<div class=\"page\" style=\"text-align: center;\" title=\"Page 1\">\n<div class=\"layoutArea\">\n<div class=\"column\">\n<p>During a certain period of time, the angular position of a swinging door is described by \ud835\udf03 = 4.00 + 8.00\ud835\udc61 + 3.00\ud835\udc61!, where \ud835\udf03 is in radians and \ud835\udc61 is in seconds. Determine the angular position, angular speed, and angular acceleration of the door at \ud835\udc61 = 2.00s.<\/p>\n<p><a href=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-02.jpg\"><img fetchpriority=\"high\" decoding=\"async\" class=\"alignnone  wp-image-17264\" src=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-02-232x300.jpg\" alt=\"\" width=\"381\" height=\"493\" srcset=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-02-232x300.jpg 232w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-02-600x775.jpg 600w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-02-793x1024.jpg 793w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-02-768x992.jpg 768w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-02-1189x1536.jpg 1189w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-02-1586x2048.jpg 1586w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-02.jpg 1668w\" sizes=\"(max-width: 381px) 100vw, 381px\" \/><\/a><\/p>\n<div class=\"page\" title=\"Page 1\">\n<div class=\"layoutArea\">\n<div class=\"column\">\n<p>A rotating wheel requires 2.00 s to complete 15.0 revolutions. Its angular speed at the end of the 2.00-s interval is 85.0 rad\/s. What is the constant angular acceleration of the wheel?<\/p>\n<p><a href=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-03.jpg\"><img decoding=\"async\" class=\"alignnone wp-image-17266\" src=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-03-e1664658729233-300x203.jpg\" alt=\"\" width=\"546\" height=\"370\" srcset=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-03-e1664658729233-300x203.jpg 300w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-03-e1664658729233-600x406.jpg 600w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-03-e1664658729233-1024x693.jpg 1024w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-03-e1664658729233-768x520.jpg 768w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-03-e1664658729233-1536x1040.jpg 1536w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-03-e1664658729233.jpg 1538w\" sizes=\"(max-width: 546px) 100vw, 546px\" \/><\/a><\/p>\n<div class=\"page\" title=\"Page 1\">\n<div class=\"layoutArea\">\n<div class=\"column\">\n<p>A wheel 1.80 m in diameter lies in a vertical plane and rotates with a constant angular acceleration of 3.00 rad\/s2. The wheel starts at rest at \ud835\udc61 = 0, and the radius vector of point P on the rim makes an angle of 30.0\u00b0 with the horizontal at this time. At \ud835\udc61 = 2.00 s, find (a) the angular speed of the wheel, (b) the linear speed and acceleration of the point P, and (c) the angular position of the point P.<\/p>\n<p><a href=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-04.jpg\"><img decoding=\"async\" class=\"alignnone wp-image-17268\" src=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-04-e1664658963128-300x217.jpg\" alt=\"\" width=\"503\" height=\"364\" srcset=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-04-e1664658963128-300x217.jpg 300w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-04-e1664658963128-600x434.jpg 600w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-04-e1664658963128-1024x740.jpg 1024w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-04-e1664658963128-768x555.jpg 768w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-04-e1664658963128-1536x1111.jpg 1536w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-04-e1664658963128.jpg 1538w\" sizes=\"(max-width: 503px) 100vw, 503px\" \/><\/a><\/p>\n<div class=\"page\" title=\"Page 1\">\n<div class=\"layoutArea\">\n<div class=\"column\">\n<p>The four particles in Figure are connected by rigid rods of negligible mass. The origin is at the center of the rectangle. If the system rotates in the xy plane about the z axis with an angular speed of 4.00 rad\/s, calculate (a) the moment of inertia of the system about the z axis and (b) the rotational energy of the system.<\/p>\n<p><a href=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-05.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-17270\" src=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-05-e1664659045997-300x230.jpg\" alt=\"\" width=\"554\" height=\"425\" srcset=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-05-e1664659045997-300x230.jpg 300w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-05-e1664659045997-600x460.jpg 600w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-05-e1664659045997-1024x784.jpg 1024w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-05-e1664659045997-768x588.jpg 768w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-05-e1664659045997-1536x1176.jpg 1536w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-05-e1664659045997.jpg 1538w\" sizes=\"(max-width: 554px) 100vw, 554px\" \/><\/a><\/p>\n<div class=\"page\" title=\"Page 2\">\n<div class=\"layoutArea\">\n<div class=\"column\">\n<p>Exercise 6: Torque<\/p>\n<p>Find the net torque on the wheel in Figure about the axle through \ud835\udc42 if \ud835\udc4e = 5.0 cm and \ud835\udc4f = 15.0 cm.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<p style=\"text-align: center;\"><a href=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-06.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-17272\" src=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-06-e1664659114585-300x176.jpg\" alt=\"\" width=\"532\" height=\"312\" srcset=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-06-e1664659114585-300x176.jpg 300w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-06-e1664659114585-600x351.jpg 600w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-06-e1664659114585-1024x599.jpg 1024w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-06-e1664659114585-768x449.jpg 768w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-06-e1664659114585-1536x899.jpg 1536w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-06-e1664659114585.jpg 1538w\" sizes=\"(max-width: 532px) 100vw, 532px\" \/><\/a><\/p>\n<div class=\"page\" title=\"Page 2\">\n<div class=\"layoutArea\">\n<div class=\"column\" style=\"text-align: center;\">\n<p>Exercise 7: Relationship Between Torque and Angular Acceleration<\/p>\n<p>The combination of an applied force and a frictional force produces a constant total torque of 32.0 N.m on a wheel rotating about a fixed axis. The applied force acts for 5.00 s; during this time the angular speed of the wheel increases from 0 to 9.00 rad\/s. Find (a) the moment of inertia of the wheel, (b) the number of revolutions of the wheel during this time period.<\/p>\n<\/div>\n<p style=\"text-align: center;\"><a href=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-07.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-17274\" src=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-07-e1664659345410-300x252.jpg\" alt=\"\" width=\"539\" height=\"453\" srcset=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-07-e1664659345410-300x252.jpg 300w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-07-e1664659345410-600x504.jpg 600w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-07-e1664659345410-1024x860.jpg 1024w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-07-e1664659345410-768x645.jpg 768w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-07-e1664659345410-1536x1290.jpg 1536w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-07-e1664659345410.jpg 1538w\" sizes=\"(max-width: 539px) 100vw, 539px\" \/><\/a><\/p>\n<div class=\"page\" style=\"text-align: center;\" title=\"Page 2\">\n<div class=\"layoutArea\">\n<div class=\"column\">\n<p>Exercise 8: Work, Power, and Energy in Rotational Motion<\/p>\n<p>Big Ben, the Parliament tower clock in London, has an hour hand 2.70 m long with a mass of 60.0 kg and a minute hand 4.50 m long with a mass of 100 kg. Calculate the total rotational kinetic energy of the two hands about the axis of rotation. (You may model the hands as long thin rods.)<\/p>\n<\/div>\n<p><a href=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-08.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone  wp-image-17276\" src=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-08-211x300.jpg\" alt=\"\" width=\"438\" height=\"623\" srcset=\"https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-08-211x300.jpg 211w, https:\/\/alnojoumacademy.com\/wp-content\/uploads\/2022\/05\/Hj-08-768x1090.jpg 768w\" sizes=\"(max-width: 438px) 100vw, 438px\" \/><\/a><\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<\/div>\n<\/div>\n<p style=\"text-align: center;\">\n<\/div>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>The figure shows three small spheres that rotate about a\u00a0vertical axis. The perpendicular distance between the axis and the center of each sphere is given. Rank the three spheres according to their rotational inertia about that axis, greatest first. During &hellip; <\/p>","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"pmpro_default_level":"","footnotes":""},"categories":[153],"tags":[],"class_list":["post-15728","post","type-post","status-publish","format-standard","hentry","category-physics","pmpro-has-access"],"_links":{"self":[{"href":"https:\/\/alnojoumacademy.com\/en\/wp-json\/wp\/v2\/posts\/15728","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/alnojoumacademy.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/alnojoumacademy.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/alnojoumacademy.com\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/alnojoumacademy.com\/en\/wp-json\/wp\/v2\/comments?post=15728"}],"version-history":[{"count":4,"href":"https:\/\/alnojoumacademy.com\/en\/wp-json\/wp\/v2\/posts\/15728\/revisions"}],"predecessor-version":[{"id":17263,"href":"https:\/\/alnojoumacademy.com\/en\/wp-json\/wp\/v2\/posts\/15728\/revisions\/17263"}],"wp:attachment":[{"href":"https:\/\/alnojoumacademy.com\/en\/wp-json\/wp\/v2\/media?parent=15728"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/alnojoumacademy.com\/en\/wp-json\/wp\/v2\/categories?post=15728"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/alnojoumacademy.com\/en\/wp-json\/wp\/v2\/tags?post=15728"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}