2.2 Benefits Of Levers

Question 1

Name the two main benefits of the lever system

Answer 1

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 efforts

Question 2

How do we work out benefit of a particular lever?

Answer 2

We look at the length of two arms.
The load arm and the effort arm

Question 3

What is the load arm?

Answer 3

The distance from the load to the fulcrum is known as the load arm

Question 4

What is the effort arm?

Answer 4

The distance from the effort to the fulcrum is known as the effort arm

Question 5

What is mechanical advantage?

Answer 5

When a lever’s effort arm is longer than the load arm a lever has mechanical advantage

Levers with mechanical advantage can move large loads with a relatively small amount of effort. They have a high load force to effort ratio

Question 6

Give an example of mechanical advantage

Answer 6

When a sprinter has a short contact time with the ground and there is small force produced by muscles but it is a able to drive the full weight of the athlete off the ground

Question 7

What is mechanical disadvantage?

Answer 7

When a lever’s load arm is longer than it’s effort arm it is mechanical disadvantage. Low load force to effort ratio.

Despite operating at mechanical disadvantage, third class leaver systems are able to increase the distance covered and therefore the speed at the end of a lever arm. They can produce a larger range of movement with relatively low force

Question 8

Give an example of mechanical disadvantage

Answer 8

The long strides which can be generated quickly at the hip because a small movement near fulcrum makes a large movement where the load is

Question 9

Which lever system are working at mechanical advantage/disadvantage?

Answer 9

1st : Depends on position of fulcrum
Closer to load : Advantage
Closer to effort : Disadvantage
2nd : Advantage
3rd : Disadvantage