BIOMECHANICS 5 Flashcards
What are the four forces we can draw on a FREE BODY DIAGRAM?
Weight
Reaction
Friction
Air resistance
What is a FREE BODY DIAGRAM?
A CLEARLY LABELLED sketch showing ALL OF THE FORCES acting on a BODY at a particular moment in time.
What two forces are vertical forces?
WEIGHT
REACTION
What two forces are horizontal forces?
FRICTION
AIR RESISTANCE
Where is the arrow representing WEIGHT drawn from on a free body diagram?
Vertically downwards from the centre of mass of the body
Where is the arrow representing REACTION drawn from on a free body diagram?
Vertically up from the point of contact.
Where is the arrow representing FRICTION drawn from on a free body diagram?
Horizontally in the direction of motion from the point of contact.
Where is the arrow representing AIR RESISTANCE drawn from on a free body diagram?
Extending horizontally against the direction of motion from the centre of mass.
What does it mean when the FRICTION arrow is larger than the AIR RESISTANCE arrow?
Body is accelerating.
What does it mean when the AIR RESISTANCE arrow is larger than the FRICTION arrow?
Body is decelerating.
What does F = AR mean?
Zero net force - no motion
What does it mean when the REACTION arrow is bigger than the WEIGHT arrow?
The body is jumping.
What does R > W mean?
Body is jumping.
What does AR > F mean?
Decelerating.
What does F > AR mean?
Accelerating.
