Mechanical advantage is the term used to describe how simple machines make accomplishing work easier. Now a certain amount of work is required to move an object and the amount of work cannot be reduced.
How then does mechanical advantage reduce the amount of work you have to do when it says right here the amount of work cannot be reduced?
The transcript is provided for your convenience
Well, mechanical advantage makes work easier by changing the way work is performed. Say for instance that you need to move an object to a given vertical height and so a certain amount of work is required to move that object to that vertical height.
Now, by getting to that given height at an angle, the effort required is reduced, but the distance that must be traveled to reach the given height is increased. Although the effort required is reduced, the length of time you have to be pushing or holding that object is increased. Overall the amount of work stays the same, but overall it’s easier to accomplish that work.
A great example of this is walking up a hill, so say we have a hill right here, someone want to get to the top of this hill, but they’re down here, they could take a direct route to the top, so it’s going to be very steep, but they don’t have to walk very far. But someone else could take a longer route, a meandering route and go like this and so as they progress up the hill, beginning to walk up the hill at an angle.
They’re only increasing elevation slowly, much slower than the person ever here who took the direct route. It requires a lot less ever to walk here because they’re not happened to gain as much elevation as quickly. But the difference here is that you see how much farther they had to walk than this person because they had to go back and forth and so even though it was easier to walk up it took them longer. The same amount of work is required for both of these, however, mechanical advantage is used right here by the person walking up this hill.
It makes it easier overall for that person to walk up the hill and so there’s basically six different types of simple machines that use the concept of mechanical advantage. And those are the inclined plane, the lever, the wheel and axle, the pulley, the wedge and the screw. Those six simple machines use mechanical advantage and those simple machines can be combined together to gain even more mechanical advantage.