Physics Review Flashcards
It takes less fore to mave a limb fast through its range of motion than it does to move it more slowly due to what law?
Newton’s law of momentum
T/F: A patient’s center of gravity changes during motion
TRUE
T/F: An object is most stable when the line of gravity falls outside the base of support
FALSE
T/F: The shape and size of the base of support determines an object’s stability.
TRUE
Describe the 3 classes of levers in the body and give an example of each.
First class: fulcrum is between force and resistance; triceps; Second class: Resistance is between fulcrum and force, brachioradialis; Third class: force is between fulcrum and resistance; biceps
Describe how changing the length of a lever arm will change the force.
F = L x D
T/F: The line of pull of a muscle produces a rotator force that causes movement and a nonrotatory force that either stabilizes or destabilizes a joint.
TRUE
The greatest physiological advantage of a muscle occurs at (which length)?
Its resting length
T/F: All tissues have the qualities of elasticity, stress-strain, and fatigue.
TRUE
T/F: The only difference between torque and force is that torque produces rotation movement.
TRUE
Explain why angle of pull is important in an isometric exercise.
Maximal isometric force occurs when the muscle is positioned with a 90 degree angle of pull on the extremity.
The hamstring will provide a greater force at the knee when the hip is positioned in _________
flexion
T/F: Power and work are the same thing.
FALSE
Tissue that is deformed because of a stretch application adheres to the concept of which of the following: creep; velocity; stress-strain; none of the above; a and c only
A and c only
A body remains at a state of rest or remains in uniform mortion until an outside force acts on it. This relates to Newton’s _________________
Law of inertia
Descrive how the center of gravity changes during sporting activity and how this relates to stability.
The lower the center of gravity, the more stable an object. Activities in which arms are overhead raise center of gravity and make patient less stable.
The most efficient lever arm in the body in producing force is the
second class
T/F: Active insufficiency results if a multijoint muscle is maximally stretched
FALSE
An example of strutural fatigue in the body is which of the following: carpal tunnel syndrome, ACL Sprain, metatarsal stress fracture, all of the above, a and c only
A and c only
The quadriceps is able to produce the most force during an eccentric contraction because (of)
the series elastic componenet and parallel elastic component contribute to overall tension development
T/F: The hamstring is able to produce the most force when the hip is extended and the knee is flexed.
FALSE
Plasticity refers to the ability of a substance
to undergo permanent change in length or shape
Define strength
muscle’s ability to produce or resist force
Define work
force times distance
Define Power
work per unit time
Define velocity
Rate of change of position
Define acceleration
rate at which velocity changes
Define energy
Capacity to do work
