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B) f is the same in both cases, and r is 2L in case 2, so the torque is bigger
in case 2.
C) The torque is force times its lever arm. In this question, since gravity
always point down, the lever will be the horizontal distance between the
ball and the wall, which in both case is equal to L. Physics 211 Lecture 17, Slide 20 Preflight An object is made by hanging a ball of mass M from one end
of a plank having the same mass and length L. The object is
then pivoted at a point a distance L/4 from the end of the
plank supporting the ball, as shown below.
Is the object balanced?
A) Yes B) No, it will fall left L/4 gravity C) No, it will fall right L
M M 62% got this right Physics 211 Lecture 17, Slide 21 Act How far to the right of the pivot is the center of mass of just
A) L/4 B) L/2 C) 3L/4 x M Physics 211 Lecture 17, Slide 22 Is the object balanced?
B) B) No, it will fall left
C) C) No, it will fall right
M x A) Ball of mass M balanced at L/4 left of pivot; beam of mass M balanced
L/4 right of pivot. So system balanced.
B) because part of the plank is on the left side of the pivot so there is more
mass on the left side
C) The torque is greater on the right because the distance from the center
of mass is greater on the right. . Physics 211 Lecture 17, Slide 23 Preflight
In case 1, one end of a horizontal plank of mass M and
length L is attached to a wall by a hinge and the other end is
held up by a wire attached t...
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- Fall '10