Exam 2.1 TB Flashcards
(52 cards)
The moment arm is defined as:
The perpendicular distance from the line of action of a force to a specified axis of rotation
Torque is defined as
a. the tendency of a force to cause rotation
b. the turning effect of a force
c. the product of force and moment arm
d. all of the above
e. none of the above.
All of the above
The moment arm of the biceps brachii muscle about the elbow joint is largest when the angle at the elbow joint is approximately
90°
If I pushed a book across the table but the force was eccentric (not through the center of the book) I would create
Both linear and angular acceleration
What is the torque if a 50N force is applied 2m from the axis of rotation?
100Nm
An eccentric force
a. causes flexion
b. causes extension
c. passes through an axis of rotation
d. does not pass through an axis of rotation
e. none of the above
d. does not pass through an axis of rotation
As a joint is moved through its range of motion when strength training with free weights, such as doing the arm curl, the moment arm for the muscle crossing the joint will get
a. longer
b. shorter
c. either a or b
d. none of the above
c. either a or b
If the moment arm is 5cm and the force is 100N, the magnitude of the torque will be
5N
To determine the length of a moment arm, you would measure
a. the perpendicular distance from the axis of rotation to the force’s line of action
OR
b. the perpendicular distance from the axis of rotation to the force’s point of application
a. the perpendicular distance from the axis of rotation to the force’s line of action
In the average female, the center of gravity is located
Lower than in the average male
Which of the following motions occurs primarily in the transverse (horizontal) plane?
A pirouette.
As a football player moves from a two-point stance (standing) to a four-point stand (hands and feet on the ground)
The player’s stability has increased.
When a human body is airborne (e.g. when a person leaps through the air)
a. the body’s center of gravity follows a parabolic flight path
b. movement of the arms and legs will not influence the flight path of the center of gravity
c. air resistance influences the flight path of the center of gravity, but not significantly
d. all of the above
e. none of the above
d. all of the above
For most segments of the human body, the segmental center of gravity is located
More proximally.
Which of the following motions occurs primarily in the frontal plane?
a. running
b. cartwheel
c. a pirouette
d. all of the above
e. none of the above
b. cartwheel
The principle or law used to describe a lift is called
Bernoulli’s principle
The vertical force that always acts upward is
Buoyant force
Which shape is most conducive to optimizing lift?
a. sphere
b. foil
c. oblong
d. rectangle
e. square
b. foil
Which of the following motions occurs primarily in the sagittal plane?
a. running
b. a cartwheel
c. a pirouette
d. all of the above
e. none of the above
a. running
For a submerged object, the buoyant force acts at the
the center of volume
The concept that explains how a spinning baseball changes direction is called
The Magnus Effect
As relative velocity increases, the fluid force acting on an object increases linearly.
T or F
False
For a body to be in static equilibrium
a. all forces acting on the body must sum to zero
b. all torques acting on the body must sum to zero
c. the body must be stationary
d. all of the above
e. none of above
d. all of the above
Two forces acting on an object to cause only rotation of the object create
a force couple
