Question: Third class lever systems favor which of the following?
Answer Choices:
speed
strength
both speed and range of motion
all of the choices are correct
Answer: both speed and range of motion
Question: The relative efficiency of a lever is proportional to which of the following?
Answer Choices:
mechanical advantage of the lever
length of the force arm
length of the resistance arm
the amount of force needed to move the lever
Answer: mechanical advantage of the lever
Question: Which of the following affects the force-generating capability of a muscle?
Answer Choices:
the muscle length and cross-sectional area
the angle and distance from the joint center of the tendon attachment to bone
the velocity of muscle shortening
all of the choices affect the force-generating capability of a muscle
Answer: all of the choices affect the force-generating capability of a muscle
Question: Which of the following quantities is zero for an object in static equilibrium?
Answer Choices:
momentum
kinetic energy
both momentum and kinetic energy
neither A nor B
Answer: both momentum and kinetic energy
Question: Which of the following is a characteristic of torque?
It is a vector quantity.
Answer Choices:
It is characterized by its magnitude.
It is characterized by its direction.
All of the choices are correct.
Answer: All of the choices are correct.
Question: Which statement is true regarding moment arm?
Answer Choices:
Moment arm is largest when the angle of pull on a bone is 90°
Changes in moment arm directly affect joint muscle torque.
For torque to remain constant, more force must be produced when moment arm decreases.
Both that the moment arm is largest when the angle of pull on a bone is 90° and that changes in moment arm directly affect joint muscle torque.
all of the statements are true regarding moment arm.
Answer: all of the statements are true regarding moment arm.
Question: When a muscle contracts at a joint, which of the following affects torque?
Answer Choices:
the rotary component of the muscle force
the stabilizing component of the muscle force
the dislocating component of the muscle force
none of the choices affect torque
Answer: the rotary component of the muscle force
Question: The perpendicular distance between the line of force and the axis defines what?
Torque
Answer Choices:
Fulcrum
Moment arm
None of the choices are correct
Answer: Moment arm
Question: The relative efficiency of a lever is proportional to which of the following?
Mechanical advantage of the lever
Answer Choices:
Length of the force arm
Length of the resistance arm
The amount of force needed to move the lever
Answer: Mechanical advantage of the lever
Question: A 30 kg child sits on the right end of a see-saw 1 m from the axis. If a 20 kg child sits on the left end of the see-saw 2 m from the axis, what will happen?
Answer Choices:
the see-saw will rotate clockwise
the see-saw will rotate counterclockwise
the see-saw will balance
need more information to predict outcome
Answer: the see-saw will rotate counterclockwise