Home Page | Input vs. Output Forces | Mechanical Advantage | Ideal Mechanical Advantage | Mechanical Efficiency | Practice Questions | Challenge Questions | Interactive Quiz | Bibliography Mechanical advantage is the ability to make work easier using a machine. When a machine multiplies an input force to produce an output force, a mechanical advantage (MA) is created. The ratio of the output force (Fout) to the input force (Fin) determines a machine's MA. If the output force is bigger than the input force, a machine has a mechanical advantage greater than one. The formula to calculate MA is output force/input force or Fout/Fin. Since MA is the ratio of two forces both measured in Newtons, there are no scientific units to measure MA. Example: If a wheelbarrow increases an input force of 100N to an output force of 300N, the MA is 3. MA = Fout/Fin MA = 300N/100N MA = 3 The greater a machine's MA, the less force is required to move the load. But applying less force doesn't mean that less work is done. For example, if you lift a box using ramp, you would use less force but you would have to travel a longer distance. Some machines have a mechanical advantage of less than one because it requires more force applied to the machine than the output force. These machines allow the output force to be exerted over a greater distance. An example would be a hockey stick because a player can move one end of the stick slightly, and the other end will move a greater distance.
Home Page | Input vs. Output Forces | Mechanical Advantage | Ideal Mechanical Advantage | Mechanical Efficiency | Practice Questions | Challenge Questions | Interactive Quiz | Bibliography
Mechanical advantage is the ability to make work easier using a machine. When a machine multiplies an input force to produce an output force, a mechanical advantage (MA) is created. The ratio of the output force (Fout) to the input force (Fin) determines a machine's MA. If the output force is bigger than the input force, a machine has a mechanical advantage greater than one. The formula to calculate MA is output force/input force or Fout/Fin. Since MA is the ratio of two forces both measured in Newtons, there are no scientific units to measure MA.
Example: If a wheelbarrow increases an input force of 100N to an output force of 300N, the MA is 3.
MA = Fout/Fin
MA = 300N/100N
MA = 3
The greater a machine's MA, the less force is required to move the load. But applying less force doesn't mean that less work is done. For example, if you lift a box using ramp, you would use less force but you would have to travel a longer distance.
Some machines have a mechanical advantage of less than one because it requires more force applied to the machine than the output force. These machines allow the output force to be exerted over a greater distance. An example would be a hockey stick because a player can move one end of the stick slightly, and the other end will move a greater distance.
Some machines have a mechanical advantage that is approximately 1. These types of machines change the direction of the input force so that the output force is going in the opposite direction. An example of this would be a fixed pulley. When you pull the rope downwards, the load is lifted upwards.
Khan Academy Explaining Mechanical Advantage (part 1 - 10 min 2 sec, part 2 - 6 min 50 sec, part 3 - 10 min 34 sec):
Links to YouTube:
youtube.com/watch?v=pfzJ-z5Ij48 - Introduction to mechanical advantage
youtube.com/watch?v=DiBXxWBrV24 - Mechanical Advantage (part 2)
youtube.com/watch?v=vSsK7Rfa3yA - Mechanical Advantage (part 3)
Home Page | Input vs. Output Forces | Mechanical Advantage | Ideal Mechanical Advantage | Mechanical Efficiency | Practice Questions | Challenge Questions | Interactive Quiz | Bibliography