# Does the fulcrum of a 2nd or 3rd class lever have to be at the end? If so why? [closed]

Here are the usual three classes of levers:

Does the fulcrum of a 2nd or 3rd class lever have to be at the end? If so why? Why not have just a little bit more board beyond it? Why right at the end?

## closed as unclear what you're asking by Kyle Kanos, Jon Custer, Yashas, David Hammen, honeste_vivereJul 17 '17 at 17:17

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

• Is the fulcrum of your wheelbarrow lever at the absolute end? – DJohnM Jul 14 '17 at 3:57
• It's like that because it's been made like that. One to act as a speed multiplier (3rd class, as mechanical advantage is always <1), and one to act as a force multiplier (2nd class, as mechanical advantage is always >1). – Wrichik Basu Jul 14 '17 at 4:56
• I'm a little unclear on what the question here is - the 2nd and 3rd class are defined by the load and the applied force being on the same side of the fulcrum. Whether the physical implementation of such a lever extends beyond the fulcrum to the other side makes no difference to this physical situation. What exactly is the question? – ACuriousMind Jul 14 '17 at 9:51
• Side note: the link to the source does not appear to work. – ZeroTheHero Jul 14 '17 at 11:58
• @ACuriousMind in some of the sources I googled, they seem to suggest that the fulcrum must be at the end. I am asking is it required to be at the end? Or is it just that the two forces must be on the same side? – Stan Shunpike Jul 15 '17 at 1:57

Speaking practically, it would make no difference the Fulcrum need not to be at the far end of the machine, to be a Second Class or Third Class Lever, as long as the Load is situated in between and Effort at the other end, that is the Effort Arm (distance between Fulcrum and Effort) is longer than the Load Arm (distance between Load and Effort) the Lever is a Second Class or if the effort is in between and load at the other end, then a Third Class Lever, in case any extra part is present beyond the Fulcrum in a second class or third class lever, that extra part is excluded or included in the Lever and does not make any difference.

Because, if we were to make calculations about certain quantities like Mechanical Advantage, Velocity Ratio, Efficiency of the lever, we would make calculations from the point at which the Fulcrum is located. Let us consider, the Fulcrum of a Second Class Lever is not situated at the far end but is somewhat away from the end. The Load is present in between. Now if we were to calculate the Mechanical Advantage of the Lever :-