Deck 11: Angular Kinematics of Human Movement

Question 1

If the angular velocity of a batter's shoulders increases, what will happen to the linear velocity of the end of the bat?

A) increase
B) decrease
C) stay the same
D) end of the bat has no linear velocity

Answer 1

increase

Question 2

An angle formed by a body segment with respect to horizontal is what?

A) relative angle
B) absolute angle
C) acute angle
D) none of the above

Answer 2

absolute angle

Question 3

If angular acceleration is constant, which of the following is true of angular velocity?

A) it must be constant
B) it must be equal to zero
C) it must be increasing
D) none of the above

Answer 3

none of the above

Question 4

Which of the following expressions defines angular velocity?

A) change in angular position over a given time
B) angular displacement divided by time
C) both A and B
D) neither A nor B

Question 5

Which of the following terms describes the angle formed between the longitudinal axes of two adjacent body segments?

A) the static angle
B) the relative angle
C) the absolute angle
D) none of the above

Question 6

During a baseball pitch, a pitcher's arm rotates through 80 degrees of motion at the shoulder. If this is accomplished in 0.5 seconds, which of the following statements is true?

A) angular velocity is constant
B) angular acceleration is constant
C) both A and B must be true
D) neither A nor B must be true

Question 7

If angular acceleration is constant, then angular velocity must be

A) constant
B) increasing or decreasing
C) equal to zero
D) none of the above

Question 8

If all other factors are held constant, what effect would "choking up" on a bat have on the resultant linear velocity of a hit ball?

A) increase
B) decrease
C) remain the same
D) need more information

Question 9

Which of the following is/are vector quantity(s)?

A) angular velocity
B) angular acceleration
C) both A and B
D) neither A nor B

Question 10

Human body angles may be calculated using which of the following?

A) goniometer
B) flexometer
C) electrogoniometer
D) all of the above

Question 11

Which angular direction is conventionally regarded as positive?

A) clockwise
B) counterclockwise
C) flexion
D) extension

Question 12

Range of motion at a joint is a measurement of what?

A) linear displacement
B) angular displacement
C) linear velocity
D) angular velocity

Question 13

Which of the following terms describes the location of the center of rotation at a joint at a given instant in time?

A) precise center
B) exact center
C) instant center
D) none of the above

Question 14

What quantity will have the following units? rad/s

A) linear displacement
B) angular displacement
C) linear velocity
D) angular velocity

Question 15

Which of the following quantities are equal?

A) 2π radians and 360°
B) 270° and 3/4 revolution
C) both A & B
D) none of the above

Question 16

Which of the following are scalar quantities?

A) angular distance
B) angular velocity
C) both A and B
D) neither A nor B

Question 17

Which of the following is not a valid unit of angular velocity?

A) radians per second
B) revolutions per minute
C) degrees per hour
D) gradients

Question 18

Which of the following is/are true regarding a radian?

A) it is equal to 57.3 degrees
B) it is the size of the angle subtended by an arc of radius length
C) it is a unit of angular displacement
D) all of the above are true

Question 19

The component of angular acceleration directed toward the center of curvature defines what?

A) radial acceleration
B) tangential acceleration
C) angular acceleration
D) linear acceleration

Question 20

A model airplane is being flown at the end of a cord 20 feet long. If the speed of the airplane remains constant, but the cord is shortened to 15 feet, what will be the effect on the radial acceleration of the airplane?

A) it will increase
B) it will decrease
C) it will remain the same
D) one must know the weight of the airplane in order to answer the question

Question 21

Which of the following can contribute to the resultant linear velocity of a projectile at release?

A) tangential acceleration
B) radial acceleration
C) both A and B
D) none of the above

Question 22

If the knee joint goes through 100° of flexion during the down phase of a squat, what is the total angular distance during 10 complete squats?

A) 1000°
B) 2000°
C) 0°
D) none of the above

Question 23

A quadruple axel (in figure skating) involves how much angular displacement?

A) 4 revolutions
B) 1440°
C) 0°
D) none of the above

Question 24

What does the letter "r" stand for in the equation v = rw?

A) resultant
B) radius of rotation
C) radian
D) none of the above

Question 25

Maximizing tangential acceleration is important in which of the following situations?

A) punting a football for distance
B) serving a tennis ball
C) throwing a dart
D) both A and B
E) all of the above

Question 26

Radial acceleration is directly affected by which of the following?

A) tangential velocity
B) radius of rotation
C) both A and B
D) none of the above

Question 27

Why is anatomical knowledge important when using a goniometer?

A) location of joint center determines placement of axis
B) bone location affects position of the goniometer arms
C) instant center of a joint can change during movement
D) both A and B
E) all of the above

Question 28

The formula v = rw establishes the relationship between what?

A) linear and angular displacement
B) linear and angular velocity
C) linear displacement and linear velocity
D) angular displacement and angular velocity

Question 29

Which of the following is/are formula(s) for tangential acceleration?

A) a_t = (v_t-v_t)/t
B) a_t = ra
C) both A and B
D) none of the above

Question 30

When observing someone lift a heavy object, which of the following is likely to be the angle of interest regarding back injury?

A) absolute angle of the trunk
B) relative angle of the trunk
C) absolute angle of the knee
D) relative angle of the knee

Question 31

What rules have to be followed when using the formula v = rw?

A) units for w have to be radian-based
B) units for v and r must the same base units (with time included in "v")
C) both A and B
D) there are no special rules

Question 32

What is the angular acceleration of the second hand on a clock after one complete revolution?

A) 6 deg/s²
B) 6 deg/s
C) 60 deg/s²
D) 0

Question 33

When angular velocity is 0, what is angular acceleration?

A) -9.81 m/s²
B) increasing
C) decreasing
D) 0
E) need more information

Question 34

When are radian-based units essential?

A) when measuring linear velocity
B) when measuring angular velocity
C) when converting between linear and angular velocity
D) all of the above

Question 35

Which of the following are appropriate units for tangential acceleration?

A) rad/s
B) m/s
C) rad/s²
D) m/s²

Question 36

When the second hand on a clock makes a complete revolution, which of the following is/are true?

A) angular distance is 360°
B) angular displacement is 0°
C) angular velocity is 6 deg/s
D) both A and B
E) all of the above

Question 37

Which of the following is/are correct units for angular speed?

A) rpm
B) deg/s
C) rad/s
D) both A and B
E) all of the above

Question 38

What component of angular acceleration represents the rate of change in direction of a rotation body?

A) tangential acceleration
B) radial acceleration
C) linear acceleration
D) none of the above

Question 39

A procedure for identifying the direction of an angular motion vector is called what?

A) right hand rule
B) clockwise rule
C) both A and B
D) no special procedure is needed

Question 40

Which of the following is a correct formula for angular velocity?

A) σ = f/t
B) w = f/t
C) w = q/t
D) σ = q/t

Question 41

A ___________________ is a unit of angular measurement equal to approximately 57.3°.

Question 42

A joint angle formed between adjacent body segments is an example of a ___________________ angle.

Question 43

The straight, full extended position of a joint is regarded as 0°.

Question 44

The symbols for linear kinematic quantities are English letters, whereas the symbols for angular kinematic quantities are ___________________ letters.

Question 45

Explain tangential acceleration using an example in sport, dance or rehabilitation.

Question 46

A ___________________ is a simple tool commonly used by clinicians to measure joint angles on human patients.

Question 47

The most common unit of time is second.

Question 48

Provide 2 examples of relative angles and 2 examples of absolute angles and explain why each would be of importance.

Question 49

Explain how to convert between degrees, radians and revolutions and give examples of when each would be appropriate units.

Question 50

Explain the concept of instant center of rotation, including a discussion of why it is important when studying human motion.

Question 51

Provide the formula which relates linear to angular velocity, including the rules that apply to the formula and an example in sport, dance or rehabilitation where the formula is applicable.

Question 52

If flexion of a joint is positive in direction when viewed from one side, the same motion will be negative in direction when viewed from the opposite side.

Question 53

The clockwise direction in rotational motions is also considered a ___________________ direction.

Question 54

Once a thrown ball is released, the tangential and radial acceleration become zero.

Question 55

When solving problems related to linear/angular conversion, the units for angular displacement must be in revolutions.