Lever Systems

Question 1

What is a 1st class lever?

Answer 1

When the fulcrum is between the effort and the load

Question 2

What is a 2nd class lever?

Answer 2

When the load is between the fulcrum and the effort

Question 3

What is a 3rd class lever?

Answer 3

When the effort is between the fulcrum and the load

Question 4

What is a lever?

Answer 4

A rigid bar (bone) that turns round a fulcrum to apply a force/effort to a load (object or weight of body)

Question 5

Give an example of a 1st class lever

Answer 5

The head when flexing and extending

Question 6

Give an example of a 2nd class lever

Answer 6

Plantar flexion of the ankle (raising up on your toes)

Question 7

Give an example of a 3rd class lever

Answer 7

Flexion at the elbow

Question 8

What is the symbol for a fulcrum?

Answer 8

A triangle

Question 9

What is the symbol for an effort?

Answer 9

An arrow

Question 10

What is the symbol for a load?

Answer 10

A square

Question 11

What are the advantages of a 2nd class lever?

Answer 11

• Provides force to lift heavy loads

- (Effort arm is longer than load arm due to the load being closer to the fulcrum than the effort)

Question 12

What are the disadvantages of a 2nd class lever?

Answer 12

• Small range of movement and cannot move quickly

Question 13

What are the advantages of a 3rd class lever?

Answer 13

• Provides speed and wide range of movement

- (Effort arm is shorter than load arm dues to effort being closer to fulcrum than load)