Bio C. 5

_________ is the change in position that occurs when all points on a body or object move in circular paths about the same fixed axis. also referred to as rotation.

_______ causes angular motion. Produced, in human, by muscles.

______ is the turning effect produced by a force. Also called______.

Torques are produced by______ or _______

External force not directed through the center of gravity of object
• Effect - cause a change in the linear and angular motion of object

Pair of forces equal in size but opposite in direction and noncolinear
• Effect - cause a change only in the angular motion of an object

The torque produced by a force is directly proportional to the:
1._________
2._________
3. ________

• The distance between the line of action of the force and the axis of rotation.
• Is the perpendicular distance between the line of action of the force and a line parallel to it that passes through the axis of rotation.

______ is a vector quantity so it therefore has magnitude and direction.
Direction is indicated by a positive (+) or negative (-) sign.

The conventional approach is to indicate _______ torques as positive (+) and ________ torques as negative (-).
More than one torque can also be added or subtracted to or from each other.

Net Torque
• Torques acting around an axis can be summed.
• if the sum of all the torques is zero then a condition known as _________ is achieved.
• If the sum of the torques acting around an axis are not zero then rotation will occur around the axis.

• Muscles create the force to turn the joints
• Torque produced by the muscle on the distal limb will cause limb to rotate in one direction.
• Muscles ability to create torque is dependent upon joint angle.

• Defined as the point at which the entire mass or weight of the body my be considered to be concentrated.
• The imaginary point that is not any one part of the body

The force of Gravity acts downward
If an external force acts on the body, the acceleration of the body caused by the force is the acceleration of the COG

Since the human body is not a rigid body, the location of the _____ depends on the position of the limbs and the distribution of mass throughout the body

______ is capacity of object to return to equilibrium or original position after being displaced
Effected by
Height of CoG
Size of base of support
Weight of object

The most stable position is the one that minimizes potential energy