College Physics
1st Edition
ISBN: 9781938168000
Author: Paul Peter Urone, Roger Hinrichs
Publisher: OpenStax College
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Textbook Question
Chapter 9, Problem 6CQ
A round pencil lying on its side as in Figure 9.13 is in neutral equilibrium relative to displacements perpendicular to its length. What is its stability displacements parallel to its length?
Figure 9.13 If the pencil is displaced too far, the torque caused by its weight changes direction to counterclockwise and causes the displacement to increase.
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A uniform plank has a mass of 4.00 kg and a length of 10.0 m. A fulcrum is placed below the plank at a
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CompreneISION
A uniform disc of mass M and radius R initially stands vertically on the
right end of a horizontal plank of mass M and length L, as shown. The
plank rests on smooth horizontal floor and friction between disc and plank
is sufficiently high such that disc rolls on plank without slipping. The plank
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The figure (a) shows an outstretched arm with
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its center of gravity is 21 cm from the
shoulder. The hand at the end of the arm
holds a 6.0-kg mass. (Figure 1)
56 cm
21 en
6.0 kg
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(b)
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the weights of the arm and the 6.0-kg mass?
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Chapter 9 Solutions
College Physics
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