Solving Lever Mechanics: Find Ideal Mechanical Advantage

AI Thread Summary
The discussion focuses on calculating the Ideal Mechanical Advantage (IMA) of a lever, where a man uses 65 N to lift a box with an effort arm of 60 cm and a resistance arm of 10 cm. The IMA is determined by the ratio of the effort arm length to the resistance arm length, which is 6 (60 cm / 10 cm). The 65 N force is not necessary for calculating the IMA, as it does not affect the ratio. The calculation shows that the IMA is unitless, as the centimeters cancel out. The conversation emphasizes the importance of understanding the formula and recognizing extraneous information in problem-solving.
billnyerocks
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Levers Please Help!

A man uses 65 N to lift a box off the ground with a lever. The effort arm is 60 cm. The resistance arm is 10 cm. What is the Ideal Mechanical Advantage?
 
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Sounds like a homework problem: the mechanical advantage is the ratio of the arm lengths. Calculate it (you need to figure out which goes on top) and tell us what you get.
 
The formula for the ideal mechanical advantage of a lever is Le divided by Lr (Lever effort over Lever resistance), which would make it 6 cm, but what is the 65 N for?
 
billnyerocks said:
The formula for the ideal mechanical advantage of a lever is Le divided by Lr (Lever effort over Lever resistance), which would make it 6 cm, but what is the 65 N for?

Some problems give you more information than you need to answer the question. The 65 N is information you do not need to find the ideal mechanical advantage.
 
Sorry about the double post, but after I posted, I read something that said to post in the homework section for homework help. Trying to follow the rules, I posted there. I thought that you could delete a post, but you can't, so I got two posts.
 
billnyerocks said:
The formula for the ideal mechanical advantage of a lever is Le divided by Lr (Lever effort over Lever resistance), which would make it 6 cm, but what is the 65 N for?
Actually, its unitless - since cm/cm cancels to 1, the units disappear.
 
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