lever system Past paper

Question 1

Class I lever

Answer 1

FULCRUM is between load(Fl) and applied force(Fa)/effort

both forces need to be in the same direction otherwise it is a propellors

Question 2

example of class I lever

Answer 2

head neck joint
load = weight of skull
fulcrum - antlanto-occipital joint
effort/applied force = trapezius and splenius capitis

Question 3

Class II lever

Answer 3

Fl is between the fulcrum and Fa

Fa Fl fulcrum

Question 4

example of class II lever

Answer 4

calf raise
load (Fl) = body weight
Effort/applied load = gastroc soleus
fulcrum= metatarsophalangeal joint

Question 5

Class III lever

Answer 5

Applied load(Fa) / effort is between fulcrum and Fl
Fl Fa fulcrum

Question 6

example class III lever

Answer 6

raising forearm and hand
load(Fl) = forearm(ulna and radius) and hand carpal bones etc
fulcrum = humeroulnar joint and humeroradial joint
applied load/effort = bicep

Question 7

mechanically advantaged means

Answer 7

greater than 1

(applied force or effort/load