Physics Review

Question 1

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?

Answer 1

Newton’s law of momentum

Question 2

T/F: A patient’s center of gravity changes during motion

Answer 2

TRUE

Question 3

T/F: An object is most stable when the line of gravity falls outside the base of support

Answer 3

FALSE

Question 4

T/F: The shape and size of the base of support determines an object’s stability.

Answer 4

TRUE

Question 5

Describe the 3 classes of levers in the body and give an example of each.

Answer 5

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

Question 6

Describe how changing the length of a lever arm will change the force.

Answer 6

F = L x D

Question 7

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.

Answer 7

TRUE

Question 8

The greatest physiological advantage of a muscle occurs at (which length)?

Answer 8

Its resting length

Question 9

T/F: All tissues have the qualities of elasticity, stress-strain, and fatigue.

Answer 9

TRUE

Question 10

T/F: The only difference between torque and force is that torque produces rotation movement.

Answer 10

TRUE

Question 11

Explain why angle of pull is important in an isometric exercise.

Answer 11

Maximal isometric force occurs when the muscle is positioned with a 90 degree angle of pull on the extremity.

Question 12

The hamstring will provide a greater force at the knee when the hip is positioned in _________

Answer 12

flexion

Question 13

T/F: Power and work are the same thing.

Answer 13

FALSE

Question 14

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

Answer 14

A and c only

Question 15

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 _________________

Answer 15

Law of inertia

Question 16

Descrive how the center of gravity changes during sporting activity and how this relates to stability.

Answer 16

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.

Question 17

The most efficient lever arm in the body in producing force is the

Answer 17

second class

Question 18

T/F: Active insufficiency results if a multijoint muscle is maximally stretched

Answer 18

FALSE

Question 19

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

Answer 19

A and c only

Question 20

The quadriceps is able to produce the most force during an eccentric contraction because (of)

Answer 20

the series elastic componenet and parallel elastic component contribute to overall tension development

Question 21

T/F: The hamstring is able to produce the most force when the hip is extended and the knee is flexed.

Answer 21

FALSE

Question 22

Plasticity refers to the ability of a substance

Answer 22

to undergo permanent change in length or shape

Question 23

Define strength

Answer 23

muscle’s ability to produce or resist force

Question 24

Define work

Answer 24

force times distance

Question 25

Define Power

Answer 25

work per unit time

Question 26

Define velocity

Answer 26

Rate of change of position

Question 27

Define acceleration

Answer 27

rate at which velocity changes

Question 28

Define energy

Answer 28

Capacity to do work