How Do You Solve These Balance Beam Problems?

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The discussion focuses on solving balance beam problems involving torque. The first problem requires calculating the distance for a 21 N weight to balance a 12 N weight located 14 cm from the fulcrum. The second problem involves determining the necessary weight to balance a 5 N weight positioned 13 cm from the fulcrum, with the new weight placed 7 cm away. Participants emphasize understanding the concept of torque and applying the relevant equations rather than simply memorizing solutions. The original poster expresses gratitude for the clarification, indicating a better understanding of the concepts.
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Need help on Practice Problems PLEASE!

Trying to work practice problems before I do the homework & I need help. If someone could show me step-by-step bow to do these two problems that would be GREAT.

A weight of 12 N is located at a distance of 14 cm from the fulcrum of a simple balance beam. At what distance from the fulcrum should a weight of 21 N be placed on the opposite side in order to balance the system?

A weight of 5 N is located 13 cm from the fulcrum on the beam of a simple balance. What weight should be placed at a point 7 cm from the fulcrum on the opposite side in order to balance the system?
 
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Welcome to PF.

I won't do them for you, but I will tell you the essence of each problem.

The first problem is torque. I assume you've got access to the equation for torque. You have a certain force, a certain distance away from a "pivotal point". And you want to figure out the distance of the other force, so that the toqrues are equal.

aaaand it looks llke the second problem is the same. You want me to tell you how to do the step by step answer so that you can memorize is and re apply it, but what happens when the problem integrates other concepts? Plus, these problems are very basic, and if you cannot do them already, or have no idea how to do them, do a bit of reading and it shouldn't be an issue.

Cheers
 


dacruick said:
Welcome to PF.

I won't do them for you, but I will tell you the essence of each problem.

The first problem is torque. I assume you've got access to the equation for torque. You have a certain force, a certain distance away from a "pivotal point". And you want to figure out the distance of the other force, so that the toqrues are equal.

aaaand it looks llke the second problem is the same. You want me to tell you how to do the step by step answer so that you can memorize is and re apply it, but what happens when the problem integrates other concepts? Plus, these problems are very basic, and if you cannot do them already, or have no idea how to do them, do a bit of reading and it shouldn't be an issue.

Cheers

thank you! i understand it now. my professor didn't explain it well.
 


right on.
 
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