Levers Paper 2

Question 1

What are the two functions of levers?

Answer 1

• To apply force (strength) to an object.

- To move the load a greater distance or through a greater range of movement.

Question 2

What are the types of levers?

Answer 2

1st class levers
2nd class levers
3rd class levers

Question 3

What is in the middle at a first class lever?

Answer 3

Fulcrum

Question 4

What is in the middle at a second class lever?

Answer 4

Load

Question 5

What is in the middle at third class levers?

Answer 5

Effort

Question 6

Give an example of a first class lever in the body.

Answer 6

Dumbbell tricep extensions (elbow extension)

Question 7

Give an example of a second class lever in the body.

Answer 7

Calf raises (plantar flexion at the ankle)

Question 8

Give an example of a third class lever in the body.

Answer 8

Dumbbell curls (elbow flexion)

Question 9

What are the two main benefits of levers?

Answer 9

1. ) Large loads can be moved with a relatively small amount of effort.
2. ) The distance a load can be moved, or the speed with which it can be moved, can be increased without an increase in effort.

Question 10

What is a ‘load arm?’

Answer 10

The distance from the load to the fulcrum

Question 11

What is an ‘effort arm?’

Answer 11

The distance from the effort to the fulcrum.

Question 12

What is a mechanical advantage?

Answer 12

• When a lever’s effort arm is longer than it’s load arm. Levers with mechanical advantage can move large loads with less effort.
• 2nd class levers

Question 13

Give an example of a second class lever with a mechanical advantage?

Answer 13

The take-off in long jump: The effort produced by the muscles, which is relatively small, is able to drive the full weight of the athlete off the ground.

Question 14

What is a mechanical disadvantage?

Answer 14

When a lever’s load arm is longer than it’s effort arm. Whilst they are said to be a ‘disadvantage’, third class levers are able to increase the speed at the end of the lever arm.

Question 15

Give an example of a third class lever with a mechanical disadvantage.

Answer 15

Hip joint: The hip joint is at a mechanical disadvantage as it has to apply a greater force to lift the load.

Question 16

When is a first class lever at a mechanical advantage?

Answer 16

• When the fulcrum is closer to the load.

- A small amount of effort will result in more powerful movements of the load.

Question 17

When is a first class lever at a mechanical disadvantage?

Answer 17

• When the fulcrum is closer to the effort.

- More effort is needed to move the load, but it can be moved at a higher speed.

Question 18

What are the benefits of a first class lever?

Answer 18

Can increase both effort and the speed of a body.

Question 19

What are the benefits of second class levers?

Answer 19

Tend only to increase the effect of the effort force.

Question 20

What are the benefits of third class levers?

Answer 20

Can be used to increase the speed of a body.

Question 21

Shoulder, elbow, hip and knee joints are…

Answer 21

3rd class levers

Question 22

An ankle joint is a….

Answer 22

2nd class lever

Question 23

Extension of the elbow joint only is a…..

Answer 23

1st class lever