Kinetics Flashcards
(30 cards)
Type, location, magnitude, direction, and rate of motion/ change determine and describe what?
Motion.
What are kinetics?
forces within the body and outside the body that affect how the body moves.
When you drop you pen or roll a ball, what type of motion occurs?
Translatory motion because they all go in a linear displacement until acted on by an outside force (Newtons 1st law).
Rotary motion is?
Motion around an axis.
Ex. Flexing and extending your elbow.
How is rotary motion measured? Linear?
Rotary motion is measured in torque and degrees.
Linear motion is measure in meters or feet.
What is velocity?
The rate at which motion occurs. how fast you are moving. Measured in (translatory m/s and rotary d/s)
The rate at which velocity changes is its____?
Acceleration.
Positive acceleration is moving faster.
Negative acceleration is slowing down.
Measured in m/s^2 or d/s^2
What is a force?
A push or a pull that causes displacement.
What is it called when a motion occurs due to a force applied to the body?
Displacement.
Torque cause motion around what?
A rotary axis.
What four forces affect body motion?
Gravity, muscles, external resistance, friction.
What is force measured in?
Newtons or kg*m/s^2.
Moment is?
Force acting at distance from axis.
M= f X d.
Newtons first law states what?
Inertia.
An body in motion will stay in motion and an body at rest will remain at rest until acted on by an outside force.
Acceleration is which one of Newtons Laws? What does it state?
Newtons Second Law.
Acceleration is proportionate to the magnitude of the net forces acting on it and inversely proportionate to the mass of the body.
Newtons third law states what?
For every action, there is an equal and opposite reaction force.
Ex. if we push onto a wall, the wall “pushes back” to resist the force we are exerting to remain stable and not break.
What does a vector diagram show?
Force and direction of an object.
Where is the axis of rotation located in a first class lever? What is an example of this?
In the middle of the force and resistance arms.
Ex. A seesaw and the adlanto occipital joint.
The axis of rotation is at the end of the system and the force arm is larger than the resistance arm in what lever?
The second class lever. An example is a wheel barrel and the gastroc. This is better for large amounts of force, such as our body weight when walking with it having more of a mechanical advantage.
Which is the most common lever in the body and what is it designed to do?
The third class lever is designed to produce speed in distal segments. The axis of rotation is at the end of the lever and the force is smaller than the resistance arm (the opposite of class two levers)
What does this equation show the ratio of? MA = force arm length/ resistance arm length.
Mechanical advantage.
Is torque force greater closer to the axis or further away?
Torque produces more force further from the axis due to its mechanical advantage.
A point where an object is balanced (typically S2) is called?
Center of mass.
In stable equilibrium, can the object return to its previous position?
Yes.
