Term
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Definition
| an extended line drawn collinear with the force |
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Term
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Definition
| the distance "l" between the line of action & the axis of rotation, measured on a line that is perpendicular to both |
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Term
| What is the direction of torque? |
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Definition
| the torque "tau" is positive when the force tends to produce a counterclockwise rotation about the axis, & negative when the force tends to produce a clockwise rotation |
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Term
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Definition
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Term
| Can the same magnitude produce different torques? |
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Definition
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Term
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Definition
| forces from external agents; the only forces used when calculating the net force |
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Term
| When is a rigid body in equilibrium? |
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Definition
| if it has zero translational acceleration & zero angular acceleration; the sum of the externally applied forces is zero & the sum of the externally applied torques is zero |
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Term
| Why is the choice of axis arbitrary in equilibrium? |
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Definition
| if an object is in equilibrium, it is in equilibrium with respect to any axis whatsoever |
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Term
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Definition
| a definite point chosen at which the weight acts on an object for the purpose of calculating the torque |
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Term
| Where does the center of gravity lie for any symmetrically shaped & uniform object? |
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Definition
| at its geometrical center |
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Term
| SI unit of moment of inertia |
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Definition
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Term
| What requirement must be met in order to use the rotational analog of Newton's second law for a rigid body rotating about a fixed axis (sum of the torques = moment of inertia x angular acceleration) |
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Definition
| alpha must be expressed in rad/s^2 |
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Term
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Definition
| the distances that locate each particle do not change during the rotational motion |
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Term
| When calculating the sum of the torques, it is necessary to include only the _____, those applied by agents outside the body |
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Definition
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Term
| What requirement must be met to determine rotational work (rotational work = constant torque x angle) |
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Definition
| theta must be expressed in radians |
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Term
| SI unit of rotational work |
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Definition
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Term
| What requirement must be met to determine to rotational kinetic energy (rotational kinetic energy = 1/2(moment of inertia x angular speed^2)) |
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Definition
| omega must be expressed in rad/s |
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Term
| SI unit of rotational kinetic energy |
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Definition
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Term
| What is the analogous concept to linear momentum in terms of rotational motion? |
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Definition
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Term
| What requirement must be met to determine the angular momentum (angular momentum = moment of inertia x angular velocity) |
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Definition
| omega must be expressed in rad/s |
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Term
| SI unit of angular momentum |
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Definition
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Term
| principle of conservation of angular momentum |
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Definition
| the total angular momentum of a system remains constant if the net average external torque acting on the system is zero; total angular momentum of a system is conserved |
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