Biomechanics - angular motion

Question 1

What is the difference between linear velocity and angular velocity/angular displacement?

Answer 1

linear velocity = biomechanics around a centre of mass
angular velocity = biomechanics around a joint

Question 2

How many degrees are there in 1 revolution (rev)?

Answer 2

360

Question 3

What is 2π radians (rad) equivalent to?

Answer 3

a full circle (360 degrees)

Question 4

What is the equation for angular velocity?

Answer 4

angular velocity = angular displacement/time
ω = Δθ/t

Question 5

What is the equation for angular acceleration?

Answer 5

angular acceleration = change in angular velocity/time
α = Δω/t

Question 6

What is moment of inertia?

Answer 6

• rotational equivalent of mass
• resistance of a body to change its state of angular motion
• measure of the distribution of mass about an axis

Question 7

What are the 3 axes of rotation?

Answer 7

• longitudinal
• frontal
• transverse

Question 8

What is the equation for moment of inertia?

Answer 8

moment of inertia = mass x radius from axis of rotation squared
I = m r2

Question 9

What is the equation for angular momentum?

Answer 9

angular momentum = moment of inertia x angular velocity
H = I ω

Question 10

Within angular momentum what happens if angular velocity increases?

Answer 10

moment of inertia would decrease to keep angular moment constant

Question 11

Do you spin faster or slower when your closer to your axis (arms + legs in)?

Answer 11

faster

Question 12

Do you spin faster or slower when your further away from your axis (arms + legs out)?

Answer 12

slower