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What is mechanical advantage and why do we use it? In this section, we will be exploring these questions and understanding Mechanical Advantage and Ideal Mechanical Advantage. At the end of the page, there are Megan's Quizlet games and quizzes and videos that will test your knowledge!

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Mechanical Advantage

Mechanical advantage is the amount by which a machine can multiply and input force. It is determined by the ratios of the output force (F out) to the input force (F in) and the ratio of the two forces are measured in Newtons(N). However, the mechanical advantage has no units. There are three types of mechanical advantages, force, speed, and distance. but we will mostly be discussing force.

Calculation:

Mechanical advantage= Output force in Newtons/ Input force in Newtons






MA= F out/ F in

Example: Calculate the mechanical Advantage of a car jack if Josh exerts 100N on the handle of the jack and the jack applies a force of 2500N to the car.

MA=F out/ F in

MA=2500N/ 100N

MA=25

The mechanical advantage of the car jack is 25.

Introduction to mechanical advantage: Introduction to simple machines, mechanical advantage and moments.

Mechanical advantage of 1

-the input and output force are equal (effort and output are equal)

Mechanical less than 1

- the output force is less than input( output is less than effort)

Example:Tweezers

Mechanical Advantage more than 1

-the input is less than output (effort less than output)

Example: Crowbar, Car Jack

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Ideal Mechanical Advantage

Ideal Mechanical Advantage(IMA) - the mechanical advantage that has no friction

In a machine, some of the work done by the input force is converted to thermal energy by the friction in the machine. Calculate the IMA by finding the ratio between the distance over which the input force is exerted on the machine (d in) and the distance over which the output force is exerted on the object (d out)

Calculation:

Ideal Mechanical advantage= Input Distance/ Output Distance

IMA= d in/ d out

Example: Ryan uses a hammer to pull out a nail. if he moves the handle 40 cm and the nail moves 8.0 cm, what is the ideal mechanical advantage?

IMA=d in/ d out

IMA=40cm/ 8cm

IMA=5

The ideal mechanical advantage of the hammer is 5.

There is no real machine that has no friction, but ideal mechanical advantage is the closes to the real machines advantage. Tools that don't have sliding parts, don't have or have a small amount of friction. For these machines,such as levers, the mechanical advantage is very close to the ideal mechanical advantage.

Ideal mechanical advantage of 1

-the distance moved by the input force is the same as the distance moved by the output force

Example: fixed pulleys

Ideal mechanical is greater than 1

-the distance moved by the output force is less than the distance moved by the input force

Example: pulley systems,ramps

Ideal mechanical is less than 1

-the distance moved by the input force is less than the distance moved by the output force

Example: hockey sticks, baseball bats, garden rakes

Watch this video to understand further more of Ideal Mechanical Advantage

Fun Friction Fact:

A machine will never have an efficiency of 100% because of friction. Some of its energy work to overcome friction

Key Definitions:

Mechanical Advantage(MA)-amount by which a machine can multipy an input force

Ideal Mechanical Advantage(IMA)- the mechanical advantage without friction

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Finished reading? Click the links to fun quizzes that will test your knowledge or watch videos that will help you understand the unit.

Megan's MA Quiz------------------------------------------------------------------------------------------------Bill Nye And Mechanical Advantage
MA in machines Quiz---------------------------------------------------------------------------------------

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