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mechadv44
28th January 2012 - 10:58 PM
ok, I know that being further away and using a fulcrum/pivot point from an object being moved takes less energy. i.e using a 4 foot crow bar to pry open something. But i can't grasp the concept of why being further away makes it so much easier. thanks
mathman
29th January 2012 - 11:34 PM
The simplest way to look at is to use the relationship work = force x distance. When you are further away, you need to use less force to get the same amount of work done, since you are moving the fulcrum a longer distance to get the same effect.
Robittybob1
29th January 2012 - 11:42 PM
QUOTE (mathman+Jan 29 2012, 11:34 PM)
The simplest way to look at is to use the relationship work = force x distance. When you are further away, you need to use less force to get the same amount of work done, since you are moving the fulcrum a longer distance to get the same effect.

Only correction to
QUOTE
When you are further away, you need to use less force to get the same amount of work done, since you are moving the fulcrum a longer distance to get the same effect.
is that the fulcrum is not supposed to move.
Moment arm is the term to use.
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