Question 1

Which type of motion is related to the moment of inertia?&#10;A)All motion&#10;B)Curvilinear&#10;C)Linear&#10;D)Rotary

Accepted Answer

Moment of inertia is related to rotary motion, which involves rotation around an axis.

Question 2

Which of the following definitions BEST describes third-class levers?&#10;A)Designed to produce power, effort moment arm greater than resistance arm&#10;B)Designed to produce range of motion and speed&#10;C)Designed for balance, axis between effort force and resistance force&#10;D)Designed to produce work, resistance moment arm greater than effort arm

Accepted Answer

Third-class levers are designed to produce a greater range of motion and speed, with the effort applied between the fulcrum and the load. This configuration is common in the human body, such as in the biceps acting to flex the forearm.

Question 3

For a specific amount of work done by the legs when moving from a sitting to standing position, which of the following factors needs to occur to increase the power of the legs during this activity?&#10;A)Increase both work done and time needed to move by same percentage&#10;B)Increase the time needed to move from sit to stand&#10;C)Decrease both work done and time needed to move by same percentage&#10;D)Decrease the time needed to move from sit to stand

Accepted Answer

To increase the power of the legs during the activity of moving from sitting to standing while keeping the work done constant, it is necessary to decrease the time needed to move. This means that the move should be done quickly with a burst of power, which requires greater force output and therefore greater power. Therefore, the correct choice is to decrease the time needed to move from sit to stand, which is option D.

Question 4

Which of the following situations is MOST LIKELY to have the GREATEST amount of ground reaction force on the legs during walking?&#10;A)Body weight of 120 lb&#10;B)Body weight is not a factor in ground reaction forces&#10;C)Body weight of 160 lb&#10;D)Body weight of 200 lb

Accepted Answer

The greater the body weight, the greater the force acting downwards on the ground during walking, resulting in a greater ground reaction force on the legs. Therefore, a body weight of 200 lb is most likely to have the greatest amount of ground reaction force on the legs during walking.

Question 5

Which of the following definitions BEST describes second-class levers?&#10;A)Designed to produce power, effort moment arm greater than resistance arm&#10;B)Designed to produce range of motion and speed&#10;C)Designed for balance, axis between effort force and resistance force&#10;D)Designed to produce work, resistance moment arm greater than effort arm

Accepted Answer

Second-class levers are designed to produce power, with the effort moment arm being greater than the resistance arm, allowing for a mechanical advantage.

Question 6

An athlete is preparing to perform a vertical jump.What part of the jump represents the position of the MOST potential energy in the legs to perform this activity?&#10;A)Semisquat before feet leave the ground&#10;B)As feet leave the ground for the jump&#10;C)At maximal vertical height of the jump&#10;D)As the toes touch the ground as jump is initially landing

Accepted Answer

The semisquat before the feet leave the ground represents the position of the most potential energy in the legs to perform a vertical jump. This is because the muscles are stretched to their maximum length in the semisquat position, allowing for a greater potential for force production during the jump. As the athlete begins to jump and leaves the ground, the potential energy in the legs is converted into kinetic energy to propel the athlete upwards. At maximal height and during the landing phase, the potential energy in the legs is decreasing as the kinetic energy is being converted back into potential energy. As the toes touch the ground during the initial landing, the potential energy in the legs is at its lowest point as the energy has been mostly dissipated and the muscles are preparing for the next jump.

Question 7

Where is the BEST location to place a cuff weight on the lower leg to have the greatest moment of inertia for the knee joint to extend?&#10;A)At the ankle&#10;B)4 inches below the knee axis at midsection of lower leg&#10;C)2 inches below the knee axis&#10;D)At the knee joint axis

Accepted Answer

The moment of inertia increases with the square of the distance from the axis of rotation. Placing the cuff weight at the ankle, which is the farthest point from the knee joint axis, maximizes the moment of inertia for knee extension.

Question 8

Which of the following factors determines that a muscle can produce a smaller effort and be more efficient for a given workload?&#10;A)Resistance arm is considered, but not effort arm&#10;B)Effort arm is less than resistant arm&#10;C)Resistant arm and effort arm are equal&#10;D)Effort arm is greater than resistant arm

Accepted Answer

When the effort arm (distance between the applied force and the joint) is greater than the resistance arm (distance between the joint and the load), it allows the muscle to produce a smaller effort and be more efficient for a given workload. This is because the longer effort arm allows the muscle to generate greater force with less effort.

Question 9

Which of the following definitions BEST describes inertia?&#10;A)An object's resistance to change in direction or speed&#10;B)Describes the speed and direction of movement&#10;C)Rate at which an object's velocity changes over time&#10;D)Energy of an object related to its position

Accepted Answer

Inertia refers to an object's resistance to change in direction or speed. It is often described as the tendency for an object to remain in its state of motion or rest unless acted upon by an external force.

Question 10

Which of the following definitions BEST describes linear acceleration?&#10;A)An object's resistance to change in direction or speed&#10;B)Describes the speed and direction of movement&#10;C)Rate at which an object's velocity changes over time&#10;D)Energy of an object related to its position

Accepted Answer

Linear acceleration is the rate at which an object's velocity changes over time. This means that it measures how quickly an object is speeding up or slowing down in a straight line. Option A describes inertia, option B describes velocity, and option D describes potential energy.

Question 11

Which of the following definitions BEST describes velocity?&#10;A)An object's resistance to change in direction or speed&#10;B)Describes the speed and direction of movement&#10;C)Rate at which an object's velocity changes over time&#10;D)Energy of an object related to its position

Accepted Answer

The answer of Which of the following definitions BEST describes...

Question 12

Which of the following definitions BEST describes first-class levers?&#10;A)Designed to produce power, effort moment arm greater than resistance arm&#10;B)Designed to produce range of motion and speed&#10;C)Designed for balance, axis between effort force and resistance force&#10;D)Designed to produce work, resistance moment arm greater than effort arm

Accepted Answer

The answer of Which of the following definitions BEST describes...

Question 13

What type of lever system is represented by the small deltoid muscle as it raises the arm from 0&#176; to 170&#176; of shoulder flexion?&#10;A)First-class&#10;B)Second-class&#10;C)Third-class&#10;D)Fourth-class

Accepted Answer

The answer of What type of lever system is represented...

Question 14

&#10;What type of lever system is depicted in the image?&#10;A)First-class&#10;B)Second-class&#10;C)Third-class&#10;D)Fourth-class

Accepted Answer

The answer of  &#10;What type of lever system is...

Question 15

How does the patella act as an anatomical pulley to increase the efficiency of the quadriceps muscle?&#10;A)Increases the moment arm of the muscle&#10;B)Increases the resistance moment arm&#10;C)Decreases the moment arm of the muscle&#10;D)Decreases the resistance moment arm

Accepted Answer

The answer of How does the patella act as an...

Question 16

What type of lever system is represented at the forefoot when a person lifts the heels off the ground in a standing position?&#10;A)First-class&#10;B)Second-class&#10;C)Third-class&#10;D)Fourth-class

Accepted Answer

The answer of What type of lever system is represented...

Question 17

A person propelling a wheelchair wants to accelerate the chair.What factor(s) must change for this to happen?&#10;A)Force moving wheelchair will remain the same as mass in chair remains the same&#10;B)Increase mass in wheelchair while using the same force to propel chair&#10;C)Increase force moving wheelchair as mass in chair remains the same&#10;D)Decrease mass in wheelchair and force used to propel chair

Accepted Answer

The answer of A person propelling a wheelchair wants to...

Deck 4: Additional Biomechanical Principles