1. WhatisMechanicalAdvantage?? 2. Whatisthedifferencebetweenidealand Actual Mechanical Advantage? Load Force 2100N Effort Force 400N 3. CalculationPractice: a. Ammar and Tuna get stuck in the mud. They used a tree branch as a lever to lift the truck. Th

● All tools are designed and made to help accomplish a task in different ways.
● When a machine is able to transform a small amount of input force into a much
larger output force, it gives us a Mechanical Advantage.
● The mechanical advantage (MA) is the ratio of the output force to the input force:
MA = Output force / Input force
● For example, A hammer pulling a nail out of place, produces an output force 15 times greater than the input force applied on the tool, thus the hammer has a mechanical advantage of 15.
● There are no limits or units of measurement to the mechanical advantage, it is just
a comparison of input to output force. (eg. hammer is 15 x greater in force than the hand)
● Any machine is useful and provides an advantage to the user when its MA is greater than 1.

Mechanical Advantage and Levers
● A lever makes minor changes to the MA formula, rather than input and output force, the lever measures the ratio of effort arm length divided by Load arm length.
MA = Effort arm length / Load Arm Length
● The hockey stick provides the perfect example of Mechanical Advantage at work. Usually held at 4 ft handle, 1 ft load.
● If a hockey player is able to apply 20 lbs of force on the stick Using the mechanical advantage, what is the output
Force on the puck?
● What about the hammer? What measurements do We need to calculate the mechanical advantage?

Mechanical Advantage and Pulleys
● If measurements of length are not available, mechanical Advantage can also be calculated by comparing the Input and output distance.
● This is especially useful when using a pulley system for support. With a pulley system, Mechanical advantage is calculated by the input and output distance of the rope attached to the pulley. Input being the side you pull on, output being the load weight.
MA = Input distance / Output distance
● Similar to other machines, if the input distance is greater than the output distance, the mechanical advantage is greater.
● For example: A box is able to be lifted 50 cm, when a 200 cm rope is pulled. What is the mechanical advantage of this pulley?

Ideal and Actual Mechanical Advantage
● When using the measurements of Distance or effort, we are actually calculating ideal Mechanical advantage. This is the measurement of Advantages of a machine if all the input force was converted directly into output force, but not possible in real life. Why not???
● Remember the example of the hammer, even when we apply the force to the lever to take out the nail, there is resistance between the nail and wood that prevents our efforts from accomplishing our goal.
● Some of our input force is also lost as we damage and dent the wood or nail.
● Actual Mechanical Advantage is the benefit the machine really provides to us.
● Actual mechanical advantage (aMA) is measured minus the impact of weight,
slippage, friction and distortion.
aMA = Output Force / Input force

Example: Ideal vs Actual MA
25N
250N
170 cm
10 cm