Chapter 8 Quiz Flashcards
Match the linear term, impulse (Ft), to its angular analogue.
Question options:
1) Iω
2) Iα
3) Moment of inertia
4) Torque
Iω
Why does gravity not affect angular momentum?
Question options:
1) Gravity does affect angular momentum.
2) Both d⊥ = 0 and T = 0
3) d⊥ = 0
4) T = 0
Both d⊥ = 0 and T = 0
The statement “a rotating body will maintain a state of constant angular motion unless acted on by an external torque” refers to which of the following?
Question options:
1) Newton’s first law of inertia
2) Newton’s second law of acceleration
3) Newton’s third law of action/reaction
4) None of the above
Newton’s first law of inertia
Somersaulting occurs around which of the following axes of rotation?
Question options:
1) Frontal
2) Longitudinal
3) Sagittal
4) All of the above
Frontal
Why does a figure skater cross his arms tightly across the chest when performing a quadruple axel?
Question options:
1) To reduce moment of inertia
2) To increase angular velocity
3) To increase time in the air
4) Both A and B
5) All of the above
Both A and B
When a cyclist rounds a curve, where does centripetal force act?
Question options:
1) On the cyclist’s centre of gravity
2) On the tires of the cycle
3) On the ground
4) On the cycle’s centre of gravity
On the tires of the cycle
Moment of inertia is the angular analogue of which of the following?
Question options:
1) Moment of force
2) Moment of time
3) Mass
4) Surface area
Mass
Match the linear term, momentum (M = mv), to its angular analogue.
Question options:
1) Moment of inertia
2) Torque
3) Iω
4) Iα
Iω
Rotating around which of the following principal axes of rotation has the least moment of inertia (anatomical position)?
Question options:
1) Anteroposterior (sagittal)
2) Longitudinal
3) Transverse (frontal)
4) Need more information
Longitudinal
Regarding moment of inertia of the leg with respect to the hip, which of the following leg morphologies would favor a sprinter?
Question options:
1) Massive thighs and slimmer lower legs
2) Massive lower legs and slimmer thighs
3) Need more information
4) Leg morphology does not matter
Massive thighs and slimmer lower legs
Which of the following is/are accurate formula(s) for angular momentum?
Question options:
1) H = Iω
2) H = mk2ω
3) M = mv
4) Both H = Iω and H = mk2ω
Both H = Iω and H = mk2ω
What are the appropriate units for angular momentum?
Question options:
1) kg·m/s2
2) kg·m2/s
3) kg2·m/s
4) kg·m2
kg·m2/s
Why do sprint coaches stress “heel to buttocks” during sprinting?
Question options:
1) Reduces moment of inertia of the foot with respect to the ankle
2) There is no scientific basis for this coaching cue.
3) Reduces moment of inertia of the lower leg with respect to the knee
4) Reduces moment of inertia of the leg with respect to the hip
Reduces moment of inertia of the leg with respect to the hip
What will happen to angular velocity when a diver goes from a tuck position to a full layout position?
Question options:
1) Remain the same
2) Decrease
3) Need more information
4) Increase
Decrease
What will happen to angular momentum when a diver goes from a tuck position to a full layout position?
Question options:
1) Decrease
2) Increase
3) Remain the same
4) Need more information
Remain the same
Which of the following are accurate units for moment of inertia?
Question options:
1) kg·m
2) N·m
3) N·m2
4) kg·m2
kg·m2
If a pendulum stops swinging, which of the following is/are true?
Question options:
1) Angular velocity = 0
2) Angular momentum = 0
3) Both angular velocity and angular momentum equal 0
4) None of the choices is true.
Both angular velocity and angular momentum equal 0
Centripetal force is related to which of the following?
Question options:
1) Radial acceleration
2) Tangential acceleration
3) Both A and B
4) None of the choices is correct.
Radial acceleration
When knee flexion is increased, what happens to the moment of inertia of the leg about the hip?
Question options:
1) Decreased
2) Need more information
3) Increased
4) Remains the same
Decreased
Which of the following are accurate units for centripetal force?
Question options:
1) N
2) N-kg·m
3) kg·m2/s
4) kg·deg2/s
N
Which of the following acts to produce a change in angular momentum?
Question options:
1) Angular impulse
2) Moment of inertia
3) Torque
4) None of the choices is correct.
Angular impulse
Which of the following quantities increases as moment of inertia decreases during the airborne phase of a dive?
Question options:
1) Angular momentum
2) Angular velocity
3) Both A and B
4) Neither A or B
Angular velocity
If a diver goes from a full layout position to a tuck position, what will happen to his momentum?
Question options:
1) Decrease
2) Increase
3) Need more information
4) Remain the same
Remain the same
Centrifugal force is a misnomer. What is really happening when you feel a pull to the outside while rounding a curve?
Question options:
1) Centripetal force
2) Inertia
3) Both centripetal force and inertia
4) None of the choices is correct.
Inertia
How many principle axes are there for the human body?
Question options:
1) One
2) Two
3) Three
4) Four
Three
Which of the following is/are most important factor(s) affecting the magnitude of centripetal force?
Question options:
1) Mass
2) Radius of rotation
3) Tangential linear velocity
4) All of the above
Tangential linear velocity
Which of the following variables contribute to moment of inertia?
Question options:
1) T and t
2) m and k
3) F and d
4) M and v
m and k
How can a cyclist maintain balance when rounding a sharp curve?
Question options:
1) Slow down
2) Lean to the inside of the curve
3) Lean to the outside of the curve
4) Both A and B
Both A and B
Which of the following variables affects angular momentum?
Question options:
1) Linear velocity
2) Angular acceleration
3) Both linear velocity and angular acceleration
4) Neither linear velocity nor angular acceleration
Neither linear velocity nor angular acceleration
According to Newton’s 2nd Law, what is the relationship among torque, moment of inertia, and angular acceleration?
Question options:
1) T = Iω
2) I = Tα
3) α = TI
4) T = Iα
T = Iα
In the absence of external torque, which of the following will increase when moment of inertia decreases?
Question options:
1) Angular momentum
2) Angular velocity
3) Both angular momentum and angular velocity
4) None of the choices will increase when moment of inertia decreases
Angular velocity
Which of the following best describes the centripetal forces experienced by a baserunner weighing 70 Newtons and a baserunner weighing 50 Newtons?
Question options:
1) The centripetal force exerted on the heavier baserunner will be greater.
2) The heavier baserunner will not be able to run as fast around the bases due to a greater centripetal force.
3) If the baserunners run at the same velocity around the bases, the heavier baserunner will have to lean in more towards the pitcher’s mound due to a greater centripetal force.
4) All of the choices are true.
If the baserunners run at the same velocity around the bases, the heavier baserunner will have to lean in more towards the pitcher’s mound due to a greater centripetal force.
When a discus thrower spins and then releases the discus, what direction will it travel?
Question options:
1) Will continue in circular path
2) Tangent to the circular path at beginning of spin
3) Tangent to the circular path at release
4) Need more information
Tangent to the circular path at release
Where is radius of gyration located in relation to centre of gravity (COG)?
Question options:
1) Need more information
2) Same distance from the axis
3) Closer to the axis
4) Further from the axis
Further from the axis
Which of the following accurately describes the radius of gyration of the forearm segment?
Question options:
1) It is greater with respect to the wrist than with respect to the elbow.
2) Need more information
3) It is greater with respect to the elbow than with respect to the wrist.
4) It is equal with respect to the wrist and with respect to the elbow.
It is greater with respect to the wrist than with respect to the elbow.
Why are golf club heads weighted?
Question options:
1) To decrease the moment of inertia of the club with respect to the shoulder
2) To increase the moment of inertia of the club head rotating around the shaft
3) To decrease the moment of inertia of the club head rotating around the shaft
4) To increase the moment of inertia of the club with respect to the shoulder
To increase the moment of inertia of the club head rotating around the shaft
