Soc 20- Levers

Question 1

What is a lever?

Answer 1

● In your body, the term ‘lever’ refers to a system of
muscles and bones working together to bring
about movement.

● When you exercise, your muscles pull on your
bones, and your bones create movement, acting
as levers.

Question 2

How does a lever work?

Answer 2

lever is a structure that has four components:

1) Fulcrum - (or pivot) - the point around which the lever
rotates (joints).

2) Load - the force that is applied by the lever system
(resistance/ object).

3) Effort - a force that is applied by the user of the lever
system (muscles).

4) Lever arm - a rigid bar such as a bone.

Question 3

What shape represents a Fulcrum

Answer 3

Traingle

Question 4

What shape represents the load

Answer 4

Square

Question 5

What shape represents the effort

Answer 5

Arrow

Question 6

What are levers classified by

Answer 6

Levers are classified according to the placement of the
fulcrum, load and effort. This affect how the levers
operates.

Question 7

Three different classes of levers

Answer 7

● 1) First class
● 2) Second class
● 3) Third class

Question 8

How do we know which type of lever it is?

Answer 8

To recall the order of the levers use the term ‘FLE’ - this will help you to remember which part of the lever is in the middle.

First class lever - Fulcrum is in the middle.

Second class lever - Load is in the middle.

Third class lever - Effort is in the middle.

Question 9

First class levers
The fulcrum sits in the middle, between the load and the effort.

Answer 9

The fulcrum sits in the middle, between the load and the effort.

For example a tricep dip-The elbow is the fulcrum which sits between the load (bodyweight)
and the effort applied by the tricep.

Question 10

Second class levers

Answer 10

The load sits in the middle, between the fulcrum and the effort.

For example- Calf Raiser
The body weight (load) sits between the toes and the ball of the
feet (fulcrum) and the gastrocnemius muscles apply the effort
by pulling the heel.

Question 11

Third class levers

Answer 11

The effort sits in the middle, between the fulcrum and the load.

For example- Bicep curl
The effort is applied by the bicep, which is between the fulcrum
at the elbow joint and the weight in your hands (load).

Question 12

Mechanical advanatages

Answer 12

large load can be lifted with a relatively
small amount of effort.

Question 13

Mechanical advantages happening

Answer 13

This happens when the output of the lever is greater
than the input - the load is greater than the effort, so
you are getting more out than you are putting in.

Question 14

First and second class levers work at ?

Answer 14

First and second class levers both work at a
mechanical advantage.

Question 15

Mechanical disadvantages

Answer 15

Third class levers cannot lift as heavy a load
with the same amount of effort, due to the position of
the effort and load from the fulcrum.

Question 16

Third class levers work at a?

Answer 16

Third class levers work at a mechanical disadvantage.

Question 17

First class lever

Answer 17

First class lever
Fulcrum in the middle
Examples: Tricep dip / nodding your head
Work at a mechanical advantage

Question 18

Second class levee

Answer 18

Second class lever
Load in the middle
Examples: Calf raises / using a wheelbarrow
Work at a mechanical advantage

Question 19

Third class lever

Answer 19

Third class lever
Effort in the middle
Examples: Tricep dip / nodding your head
Work at a mechanical disadvantage

Question 20

Mechanical advantage

Answer 20

Input>Output

Question 21

Mechanical disadvantage

Answer 21

Input<Output