Levers

Question 1

What are the different parts of a lever system?

Answer 1

Lever
Fulcrum
Effort
Load

Question 2

What acts as a lever in the body?

Answer 2

Bones

Question 3

What acts as a fulcrum in the body?

Answer 3

Joints

Question 4

What acts as the effort in the body?

Answer 4

Muscles

Question 5

What acts as a load in the body?

Answer 5

Body weight / weight of limb / weight of something they are holding

Question 6

What are the 3 classes of lever?

Answer 6

1st class, 2nd class, 3rd class

Question 7

Draw a 1st class lever

Answer 7

Question 8

Draw a 2nd class lever

Answer 8

Question 9

Draw a 3rd class lever

Answer 9

Question 10

Give a detailed example of two first class levels in the body?

Answer 10

Extension of the neck when preparing to head a ball in football
Fulcrum=neck, effort=trapezius, load=cranium

Extension of the elbow during a bicep curl
Fulcrum=elbow, effort=biceps brachii, load=forearm/weight in hand

Question 11

Give a detailed example of a 2nd class lever in the body

Answer 11

Plantarfelxion of the ankle when taking off in high jump
Fulcrum=ankle, effort=gastrocnemius, load=bodyweight

Question 12

Give a detailed example of two third class levers in the body

Answer 12

Upwards phase of a bicep curl
Fulcrum=elbow, effort= biceps brachii, load=forearm/weight in hand

Extension of knee when kicking a football
Fulcrum=knee, effort=quadriceps, load=lower leg

Question 13

What does the term ‘effort arm’ mean?

Answer 13

The distance between the effort and the fulcrum

Question 14

What does the term ‘load arm’ mean?

Answer 14

The distance between the load and the fulcrum

Question 15

What is meant by a mechanical advantage?

Answer 15

A large load can be moved with a relatively small effort

Question 16

Which class of lever always has a mechanical advantage?

Answer 16

A 2nd class lever system always has a mechanical advantage as the effort arm is always greater than the load arm

Question 17

What is meant by a mechanical disadvantage?

Answer 17

A large effort is required to move a relatively small load

Question 18

Which class lever always has mechanical disadvantage?

Answer 18

A 3rd class level system will always have mechanical disadvantage as the load arm is always bigger than the effort arm

Question 19

What is the advantage of having a third class level?

Answer 19

A 3rd class level can move a load at a high velocity over a large range of movement.