Engineering Mechanics
14th Edition
ISBN: 9780133951929
Author: HIBBELER, Russell C.
Publisher: Pearson Education
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Chapter 19.2, Problem 1P
The rigid body (slab) has a mass m and rotates with an angular velocity ω about an axis passing through the fixed point O Show that the momenta of all the particles composing the body can be represented by a single
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5) In ice figure skating, a couple execute a “top” (see picture). The centre of mass of the woman (58 kg) is situated 1.3 m from the axis of rotation which is vertical and passes through the centre of mass of the man (85 kg). They are spinning at a constant angular velocity equal to 3.1415 rad/s and the man and woman have moments of inertia, about their own centres of mass, equal to 1.6 and 2.5 kg.m2 respectively. Then the woman grabs the neck of the man. At this point, her moment of inertia decreases to 1.4 kg.m2 and her body centre of gravity is 0.9 m from the axis of rotation. Determine the new angular velocity.
Hints: This is a conservation of angular momentum problem, and needs the parallel axis theorem to determine moments of inertia about the axis of rotation. The skaters are moving as one body with one angular velocity, but they each have their own moments of inertia given relative to their own CoMs. For the man, that’s fine…the axis they’re rotating about passes through his…
Chapter 19 Solutions
Engineering Mechanics
Ch. 19.2 - Determine the angular momentum of the 100-kg disk...Ch. 19.2 - Determine the angular impulse about point O for t...Ch. 19.2 - If it is subjected to a couple moment of M = (3t2)...Ch. 19.2 - The 300-kg wheel has a rad1us of gyration about...Ch. 19.2 - If rod OA of negligible mass is subjected lo the...Ch. 19.2 - Gears A and B of mass 10 kg and 50 kg have radii...Ch. 19.2 - The 50-kg spool is subjected to a horizontal force...Ch. 19.2 - The reel has a weight of 150 lb and a radius of...Ch. 19.2 - The rigid body (slab) has a mass m and rotates...Ch. 19.2 - At a given Instant, the body has a linear momentum...
Ch. 19.2 - Show that if a slab is rotating about a fixed axis...Ch. 19.2 - The 40-kg disk is rotating at = 100 rad/s. When...Ch. 19.2 - The Impact wrench cons1sts of a slender 1-kg rod...Ch. 19.2 - The airplane is traveling in a straight line with...Ch. 19.2 - The double pulley consists of two wheels which are...Ch. 19.2 - The assembly weighs 10 lb and has a radius of...Ch. 19.2 - The disk has a weight of 10 lb and is pinned at...Ch. 19.2 - The 30-kg gear A has a radius of gyration about...Ch. 19.2 - Determine the angular velocity of the pulley when...Ch. 19.2 - The 40-kg roll of paper rests along the wall where...Ch. 19.2 - The slender rod has a mass m and is suspended at...Ch. 19.2 - The rod of length L and mass m lies on a smooth...Ch. 19.2 - A 4-kg disk A is mounted on arm BC. which has a...Ch. 19.2 - The frame of a tandem drum roller has a weight of...Ch. 19.2 - The 100-lb wheel has a radius of gyration of kG =...Ch. 19.2 - The 4-kg slender rod rests on a smooth floor If it...Ch. 19.2 - The double pulley consists of two wheels which are...Ch. 19.2 - The 100-kg spool is resting on the inclined...Ch. 19.2 - The spool has a weight of 30 lb and a radius of...Ch. 19.2 - The two gears A and B have weights and radii of...Ch. 19.2 - The hoop (thin ring) has a mass of 5 kg and is...Ch. 19.2 - The 30-kg gear is subjected to a force of P =...Ch. 19.2 - The 30-lb flywheel A has a radius of gyration...Ch. 19.2 - If the shaft is subjected to a torque of M = (...Ch. 19.2 - The double pulley consists of two wheels which are...Ch. 19.2 - The crate has a mass mc. Determine the constant...Ch. 19.4 - The turntable T of a record player has a mass of...Ch. 19.4 - The 10-g bullet having a velocity of 800 m/s is...Ch. 19.4 - The 10-g bullet having a velocity of 800 m/s is...Ch. 19.4 - The circular disk has a mass m and is suspended at...Ch. 19.4 - The 80-kg man is holding two dumbbells while...Ch. 19.4 - The platform swing consists of a 200-lb flat plate...Ch. 19.4 - The 2-kg rod ACB supports the two 4-kg disks at...Ch. 19.4 - The satellite has a mass of 200 kg and a radius of...Ch. 19.4 - Disk A has a weight of 20 lb. An inextensible...Ch. 19.4 - The plank has a weight of 30 lb, center of gravity...Ch. 19.4 - The 12-kg rod AB is pinned to the 40-kg disk. If...Ch. 19.4 - A thin rod of mass m has an angular velocity o...Ch. 19.4 - Tests of impact on the fixed crash dummy are...Ch. 19.4 - The vertical shaft is rotating with an angular...Ch. 19.4 - The mass center of the 3-lb ball h3s a velocity of...Ch. 19.4 - Prob. 44PCh. 19.4 - The 10-lb block is sliding on the smooth surface...Ch. 19.4 - Determine the height hat which a billiard ball of...Ch. 19.4 - The pendulum consists of a 15-kg solid ball and...Ch. 19.4 - The 4-lb rod AB is hanging in the vertical...Ch. 19.4 - Determine the largest angular velocity 1 the disk...Ch. 19.4 - The solid ball of mass m is dropped with a...Ch. 19.4 - The wheel has a mass of 50 kg and a radius of...Ch. 19.4 - The wheel has a mass of 50 kg and a radius of...Ch. 19.4 - The rod of mass m and length L is released from...Ch. 19.4 - Prob. 55PCh. 19.4 - A ball having a mass of 8 kg and initial speed of...Ch. 19.4 - A solid ball with a mass m is thrown on the ground...Ch. 19.4 - The pendulum consists of a 10-lb solid ball and...Ch. 19.4 - The cable is subjected to a force of P = (10t2)...Ch. 19.4 - The space capsule has a mass of 1200 kg and a...Ch. 19.4 - The tire has a mass of 9 kg and a rad1us of...Ch. 19.4 - The wheel having a mass of 100 kg and a radius of...Ch. 19.4 - The spool has a weight of 30 lb and a radius of...Ch. 19.4 - Spool B is at rest and spool A is rotating at 6...Ch. 19.4 - A thin disk of mass m has an angular velocity 1...Ch. 19.4 - Prob. 8RP
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