Term
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Definition
•the rotary effect of a force about an axis of rotation
• measured as the product of force and the force’s moment arm - the shortest (perpendicular) distance between a force’s line of action and an axis of rotation |
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Term
| The moment arm of a force is the |
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Definition
perpendicular distance from the force’s line of action to the axis of rotation. |
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Term
Where do torques occur within the human body? |
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Definition
The product of muscle tension and muscle moment arm produces a torque at the joint crossed by the muscle. |
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Term
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Definition
•a simple machine consisting of a relatively rigid bar-like body that can be made to rotate about an axis or a fulcrum
• there are first, second, and third class levers |
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Term
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Definition
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Term
What is mechanical advantage? |
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Definition
| the ratio of the moment arm of the force (force arm) to the moment arm of the resistance(resistance arm) for a given lever |
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Term
| A force can balance a larger resistance when the force arm is longer than the |
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Definition
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Term
a____can move a resistance through a large range of motion when the force arm (Fa) is shorter than the resistance arm (Ra). |
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Definition
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Term
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Definition
•the rotary effect of a force about an axis of rotation
• measured as the product of force and the force’s moment arm - the shortest (perpendicular) distance between a force’s line of action and an axis of rotation |
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Term
What is static equilibrium? |
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Definition
•a motionless state in which there is no net force or net torque acting |
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Term
What is the center of gravity? |
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Definition
•the point around which a body’s weight is equally balanced in all directions
• also referred to as the center of mass or mass centroid
• (need not be physically located inside of a body) |
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Term
Why is the center of gravity of interest in the study of human biomechanics? |
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Definition
• it serves as an index of total body motion
Path of the center of gravity of a runner |
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Term
Why is the center of gravity of interest in the study of human biomechanics? |
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Definition
•the body responds to external forces as though all mass were concentrated at the CG
•this is consequently the point at which the weight vector is shown to act in a free body diagram |
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Term
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Definition
•resistance to disruption of equilibrium |
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Term
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Definition
| ability to control equilibrium |
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Term
What is the base of support? |
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Definition
area bound by the outermost regions of contact between a body and the support surface) |
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Term
| What can increase a body’s stability |
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Definition
•increasing body mass
• increasing friction between the body and the surfaces of contact |
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Term
| What can increase a body’s stability |
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Definition
•increasing the size of the base of support in the direction of an external force |
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Term
| What can increase a body’s stability |
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Definition
•horizontally positioning the center of gravity near the edge of the base of support on the side of the external force |
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Term
What can increase a body’s stability? |
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Definition
• vertically positioning the center of gravity as low as possible
The higher the CG, the greater the amount of torque its motion creates about the support surface.
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