Calculating Force Needed to Lift a Rock with a Crowbar

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To calculate the force needed to lift a 500 Newton rock with a 2.0 meter crowbar, the lever principle equation f1d1 = f2d2 is used, where f1 is the force applied at distance d1 from the fulcrum, and f2 is the weight of the rock at distance d2 from the fulcrum. The correct substitution gives (500 N)(2.0 meters) = (x N)(0.5 meters), leading to the solution of x = 200 N. A sketch of the situation can help clarify the distances involved. The misunderstanding about the distance from the fulcrum was addressed, confirming that the rock is indeed 0.5 meters from the fulcrum.
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What equation is used to solve a problem similar to the one below?

What force must be applied to the end of a 2.0 meter long crowbar in order to lift
a 500 Newton rock if the fulcrum of the bar is .5 meters from the rock?

Thanks.
 
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Would it be something like f1d1=f2d2?
Therefore, (500 N)(2.0 meters) = (x N)(0.5 meters). And the answer is 200 N?
 
fiosuer said:
Would it be something like f1d1=f2d2?
Therefore, (500 N)(2.0 meters) = (x N)(0.5 meters). And the answer is 200 N?

THe equation is correct.. What is means is that f1 is applied at distance d1 from the fulcrum and F2 is applied a distance d2 from the fulcrum.

I recommend that you sketch the situation to help select the correct values to substitute.
 
Fewmet said:
THe equation is correct.. What is means is that f1 is applied at distance d1 from the fulcrum and F2 is applied a distance d2 from the fulcrum.

I recommend that you sketch the situation to help select the correct values to substitute.

Is it 2.0 - 0.5 = 1.5?
(500 N)(1.5 meters) = (x N)(0.5 meters). And the answer is 1500N?
 
fiosuer said:
Is it 2.0 - 0.5 = 1.5?
(500 N)(1.5 meters) = (x N)(0.5 meters). And the answer is 1500N?

That would be true of the 500 N rock were 1.5 m from the fulcrum. THe questions says it is 0.5 m from the fulcrum.
 
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