Levers

Question 1

A lever is made up of 3 basic parts, what are these?

Answer 1

• Fulcrum
• Resistance / Load
• Effort

Question 2

Which is the simplest lever class?

Answer 2

First class, the fulcrum is in the middle.

Question 3

What is meant by the fulcrum?

Answer 3

The pivot in the system (in the body the joints are the fulcrums).

Question 4

In the human body, what acts as the fulcrum?

Answer 4

Joints.

Question 5

Where is the effort normally from?

Answer 5

It typically comes from muscle contraction.

Question 6

What technique can be used to remember the order of parts within each lever system?

Answer 6

1 2 3

F L E

Question 7

What is meant by the effort?

Answer 7

The force applied to move the resistance (usually provided by a muscle contraction).

Question 8

In the human body, what acts as the resistance?

Answer 8

Weight.

Question 9

During a lineout , what class lever system is the hooker using to throw the ball?

Answer 9

First-class:
Load (ball) behind the head,
Fulcrum (elbow) by the ears,
Effort (triceps) in front of the elbow.

Question 10

In the human body, what acts as the effort?

Answer 10

Muscles.

Question 11

What is meant by the resistance?

Answer 11

The load which is moved by a lever system.

Question 12

Which of the three parts determines which lever system is active?

Answer 12

The part in the middle.
1st = Fulcrum
2nd = Resistance
3rd = Effort

Question 13

Which lever system is active in the ankle joint?

Answer 13

Second class:
Fulcrum (toes) at the front
Resistance (weight) through the arch of the foot
Effort (calf) behind the heel

Question 14

Where in the body can a second class lever system be found?

Answer 14

Ankle joint.

Question 15

Which lever system has the resistance in the middle?

Answer 15

2nd.

Question 16

Where in the body can a third class lever system be found?

Answer 16

Elbow joint.

Question 17

Carrying a wheelbarrow is which type of lever system?

Answer 17

Second class.

Question 18

Paddling a kayak is which type of lever system?

Answer 18

Third class.

Question 19

Which lever system has the effort in the middle?

Answer 19

3rd.

Question 20

A bicep curl is which type of lever system?

Answer 20

Third class.

Question 21

Which lever system has the highest mechanical advantage?

Answer 21

Second class:

The effort arm is largest compared to the load arm.

Question 22

What is the load arm?

Answer 22

The distance of the resistance (load) to the fulcrum.

Question 23

Which lever system has the fulcrum in the middle?

Answer 23

1st.

Question 24

What is the effort arm?

Answer 24

The distance from the effort to the fulcrum.

Question 25

When is mechanical advantage high?

Answer 25

When the effort arm is longer than the load arm.

Question 26

Which lever system has the lowest mechanical advantage?

Answer 26

Third class:

The effort arm is smallest compared to the load arm.

Question 27

What are the characteristics of a high mechanical advantage?

Answer 27

They can move large loads with relatively low effort.

Question 28

Which class levers can move large loads with relatively low effort?

Answer 28

Second class.

Question 29

What are the characteristics of a low mechanical advantage?

Answer 29

They can produce a larger range of movement with relatively low effort.

Question 30

When is mechanical advantage low?

Answer 30

When the load arm is longer than the effort arm.

Question 31

Which class levers can move loads over a larger range of movement with relatively low effort?

Answer 31

Third class.

Question 32

Describe the mechanical advantage of a first class lever?

Answer 32

No advantage if the fulcrum is between the load and effort.
Higher advantage if fulcrum is closer load.
Lower advantage if fulcrum is closer to effort.

Question 33

T / F:
First class levers can have either a high or low mechanical advantage.

Answer 33

True, it is dependent on the the position of the fulcrum.