Mechanical Advantage

Effort Force (Fe)/Input force

Effort Force (Fe)/Input force

The force that is pushing/pulling an object)

Load Force/Resistance Force( Fl) or (Fr)

the force that is being acted upon/the force that is being lifted

True or False: Weight is a unit of force

True

Effort Distance:

The effort forces distance from the fulcrum

Load Distance

The load forces distance from the fulcrum

What does a mechanical advantage of 2 mean?

The effort distance is twice as large as the load distance; the load force is twice as large as the effort force

Is more effort force required if the load distance is greater?

Yes

What is mechanical advantage?

How useful or helpful a machine is;

True or False: The mechanical advantage has units

FALSE

What is Ideal Mechanical Advantage (IMA) and what is used to calculate it?

The theoretical mechanical advantage; Uses effort and load distance

What is Actual Mechanical Advantage (AMA) and what is used to calculate it?

Realistic Mechanical advantage; takes into account energy loss, wind resistance, etc. Uses effort and load force

What is the formula for AMA?

Load force divided by effort force

What is the formula for IMA

Effort distance divided by Load distance

True or False: AMA will always be greater than IMA

False; AMA will always be less than

How do you calculate the efficiency of a machine?

AMA divided by IMA; will never be 100 percent

What is considered a mechanical advantage?

If the MA is less than 1

What does a mechanical advantage of 0.25 or 1/4 mean?

4x more effort force is required; Effort distance is 4x closer to the fulcrum than the load distance

Why operate a machine with a mechanical advantage of 1?

To lift a load as high as possible with the least amount of effort

What is the mechanical advantage if the effort distance is 6 cm and the load distance is 12cm?

1/2

What is moment

Rotational force ; Force times distance

How does moment work in a first class lever?

Load force causes moment in one direction; effort force causes moment in the opposite direction

How do you increase the magnitude of a moment?

Increase the distance

How can a 4kg and 5 kg stack of bricks balance?

The 4kg stack is 5 spaces away; the 5kg stack is 4 spaces away from the fulcrum

What are characteristics of a first class lever?

The load and effort distance are on opposite sides of the fulcrum; the effort and load force are exerted in the same direction

What are characteristics of a second class lever?

The fulcrum is on the end; The load force is exerted in the middle; the effort distance is always greater than the load distance; Effort and load forces are exerted in opposite directions; Effort is on the end

What are characteristics of a third class lever?

Fulcrum is on the end; Effort and load forces are exerted in opposite directions; Effort force is always closer to the fulcrum than the load force; Load is on the end

True or False: The Mechanical Advantage of a third class lever will always be greater than 1?

False: the MA will always be less than 1 since the effort force is closer to the fulcrum

What is the MA of a second class lever?

MA>1

What class lever is the most efficient?

2nd; the effort distance is always farther away meaning less force is required to lift the load

Classify the lever?

2nd class

Classify the lever

2nd class

Classify the lever

3rd class

Classify the lever

1st class