Lecture 9

Question 1

What is a colinear force

Answer 1

Forces have the same line of action

Can be added together

Question 2

What are internal forces

Examples

Answer 2

Forces that action within the object or system

E.g. Bones, muscles, tendons, ligaments
Tension forces
Compression forces

Question 3

What are tension forces

Answer 3

Pulling forces act on the ends of an internal structure

The structure in under tension

Question 4

What are compression forces

Answer 4

Pushing forces act on the ends of an internal structure

The structure is under compression

Question 5

What happens if Tension/compression forces are greater than body structure can withstand

Examples

Answer 5

Structure fails and breaks

Muscle pull
Tendon rupture
Ligament tear
Bone breaks

Question 6

What are external forces

Example

Answer 6

Forces that act on an object as a result of ites interaction with environment

Contact force (ground)
Noncontact force (gravity)

Question 7

What is weight

Answer 7

Force of gravity pulling an object towards the center of the Earth

Question 8

What is the equation of weight or gravity

Answer 8

mass x gravity

Question 9

What is friction force

Answer 9

Force resisting the motion of two solid surfaces against each other

Friction direction is along the surface and opposite to the direction of the intended motion