The position of the elbow joint to the wrist
as it relates to the trunk is
A)
B)
C)
D)
proximal
medial
inferior
anterior
The position of the elbow joint to the wrist
as it relates to the trunk is
A)
B)
C)
D)
proximal
medial
inferior
anterior
The position of the shoulder to the elbow
as it relates to the wrist is
A)
B)
C)
D)
proximal
distal
inferior
anterior
The position of the shoulder to the elbow
as it relates to the wrist is
A)
B)
C)
D)
proximal
distal
inferior
anterior
Motion in the sagittal plane takes place
about which axis?
A)
B)
C)
D)
longitudinal
mediolateral
transverse
anteroposterior
Motion in the sagittal plane takes place
about which axis?
A)
B)
C)
D)
longitudinal
mediolateral
transverse
anteroposterior
Most human movements in running take
place in
A)
B)
C)
D)
the sagittal plane
the frontal plane
the transverse plane
multiple planes
Most human movements in running take
place in
A)
B)
C)
D)
the sagittal plane
the frontal plane
the transverse plane
multiple planes
A subject slowly bends over at the trunk. What
type of muscle action is occurring in the trunk
extensors during the activity?
A)
B)
C)
D)
E)
Concentric/Shortening
Eccentric/Lengthening
Isotonic
The extensors are not active
Isometric
A subject slowly bends over at the trunk. What
type of muscle action is occurring in the trunk
extensors during the activity?
A)
B)
C)
D)
E)
Concentric/Shortening
Eccentric/Lengthening
Isotonic
The extensors are not active
Isometric
Levers: The Law
• Fload rload = Feffort reffort
P1 vs P2: Mechanical Advantage or Disadvantage?
Feffort
A) P1-> Advantage,
P2-> Disadvantage
A) P1-> Disadvantage,
P2-> Advantage
A) P1,P2 ->
Disadvantage
P1
A) P1,P2-> Advantage
P2
A) I have no idea
Levers: The Law
• Fload rload = Feffort reffort
P1 vs P2: Mechanical Advantage or Disadvantage?
Feffort
A) P1-> Advantage,
P2-> Disadvantage
A) P1-> Disadvantage,
P2-> Advantage
A) P1,P2 ->
Disadvantage
P1
A) P1,P2-> Advantage
P2
A) I have no idea
Levers: The Law
• Fload rload = Feffort reffort
reffort = ?
reffort =
Feffort
a) 200m
b) 0.02m
100kg
c) 50m
rload
rload=1m
Feffort=my laptop (2kg)
? reffort
d) 1m
e) I don’t understand
Levers: The Law
Fload rload = Feffort reffort
reffort = ?
Feffort
reffort =
a) 200m
100kg
b) 0.02m
rload
rload=1m
Feffort=my laptop (2kg)
reffort = (Fload rload)/Feffort
reffort = (100 kg) (1m)/(2kg)
reffort = 50m
? reffort
c) 50m
d) 1m
e) I don’t understand
Lever Problems
The biceps brachii and brachioradialis are both elbow flexors, but act at
different distances from the elbow (5 cm, 20cm).
1) If I want to use the minimum amount of muscle force possible, which
muscle and how much force should I use to lift the 2kg load (15cm)? Only
one muscle can be used.
A) Biceps : 6kg
B) Brachioradialis : 1.5 kg
C) Brachioradialis : 6 kg
D) Biceps : 1.5 kg
J (Elbow)
reffort-biceps
rload
reffort-brachioradialis
Lever Problems
The biceps brachii and brachioradialis are both elbow flexors, but act at
different distances from the elbow (5 cm, 20cm).
1) If I want to use the minimum amount of muscle force possible, which
muscle and how much force should I use to lift the 2kg load (15cm)? Only
one muscle can be used.
A) Biceps : 6kg
B) Brachioradialis : 1.5 kg
C) Brachioradialis : 6 kg
D) Biceps : 1.5 kg
J (Elbow)
reffort-biceps
rload
reffort-brachioradialis
Lever Problems
The biceps brachii and brachioradialis are both elbow flexors, but act at
different distances from the elbow (5 cm, 20cm).
1) If I want to use the minimum amount of muscle force possible, which
muscle and how much force should I use to lift the 2kg load (15cm)? Only
one muscle can be used.
2) Indicate at which point along my arm I should hang the load if I want
the biceps brachii to function as a force-amplifier.
A
J (Elbow)
reffort-biceps
B
C
rload
D
reffort-brachioradialis
E: None
Lever Problems
The biceps brachii and brachioradialis are both elbow flexors, but act at
different distances from the elbow (5 cm, 20cm).
1) If I want to use the minimum amount of muscle force possible, which
muscle and how much force should I use to lift the 2kg load (15cm)? Only
one muscle can be used.
2) Indicate at which point along my arm I should hang the load if I want
the biceps brachii to function as a force-amplifier.
A
J (Elbow)
reffort-biceps
B
C
rload
D
reffort-brachioradialis
E: None
Lifting a box
Calculate how much force in the back extensor muscles is
needed when lifting a 1 kg box with the arms outstretched
(r = 30 cm), compared to when the arms are beside the
body (r = 5 cm). The muscle’s effort arm: (reffort = 5cm).
A) 6 times less force
A) 6 times more force
Draw a diagram!
A) the same force
A) 150 times more
A) I don’t understand
Lifting a box
Calculate how much force in the back extensor muscles is
needed when lifting a 1 kg box with the arms outstretched
(r = 30 cm), compared to when the arms are beside the
body (r = 5 cm). The muscle’s effort arm: (reffort = 5cm).
A) 6 times less force
A) 6 times more force
Draw a diagram!
A) the same force
A) 150 times more
A) I don’t understand