Identify class for three metal bars (Magnetic Field)

AI Thread Summary
The discussion centers on identifying the classification of three metal bars based on their magnetic properties, specifically attraction and repulsion. Classifications are not based on the materials' inherent magnetic properties but rather on classroom categories, with Class 1 containing magnets and Class 2 and Class 3 including non-magnetic materials. The interaction between classes indicates that Class 1 materials are attractive to Class 2 and Class 3, while materials within Class 2 and Class 3 show no attraction. The confusion arises in determining how to classify the bars based solely on observed magnetic behavior. Understanding these classifications is essential for solving the homework problem effectively.
jlmccart03
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Homework Statement


I need to identify which class bar 1 and bar 2 belong in based on observed attraction/repulsion. Then I need to determine if the end of 2A would attract, repel, or niether to end 3A.
upload_2017-3-14_11-16-1.png

EDIT: Could not get this image in the post due to security reason apparently so here is the link
http://imgur.com/r5QeR3z

Homework Equations


No equations needed.

The Attempt at a Solution


I am simply lost on how to even begin to understand how they determine the class. I want to say that Bar 2 is a magnet so it belongs in class 1, but
 
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Welcome @jlmccart03 to Physics Forums!

I would like to help you out with your simple problem.

But before giving you the detailed description about your answer to the problem, I would first like to tell you that the classes made in the table are not related to any metals and their respective Magnetic Properties in Nature. They simply mean a Class as in a Classroom.

Now, Let's Begin...

--The materials in the Class 1 are Magnets, Nails and Compass.
--The materials in Class 2 are Penny, Nails.
--The materials in Class 3 are Wood, Plastic, Foil and Penny.

--The table drawn below these classes represents the inter-magnetic properties of the above-listed materials. This basically means in simple words as "How would the materials from a specific Class (Row) would react to the materials of another class (Column).

--For the First case of Class1(ROW) to Class1(COLUMN), the materials contains Magnets, hence they are "ATTRACTIVE" to each other.
--For the Second case of Class1(ROW) to Class2(COLUMN), it is clear that as a magnet in class 1 is attracted to all the materials of class2, it is also named as "ATTRACTIVE".
--For the Third case of Class1 to Class3, it should be "Attractive".
--Similarly, for Class2 to Class2, "Not Attractive".
CLass2 to Class3, "Not Attractive".
and for the last one, Class 3 to class 3 itself, it should be "Not Attractive".

Hope I've answered your question appropriately.
 
Shubham Jaydeokar said:
Welcome @jlmccart03 to Physics Forums!

I would like to help you out with your simple problem.

But before giving you the detailed description about your answer to the problem, I would first like to tell you that the classes made in the table are not related to any metals and their respective Magnetic Properties in Nature. They simply mean a Class as in a Classroom.

Now, Let's Begin...

--The materials in the Class 1 are Magnets, Nails and Compass.
--The materials in Class 2 are Penny, Nails.
--The materials in Class 3 are Wood, Plastic, Foil and Penny.

--The table drawn below these classes represents the inter-magnetic properties of the above-listed materials. This basically means in simple words as "How would the materials from a specific Class (Row) would react to the materials of another class (Column).

--For the First case of Class1(ROW) to Class1(COLUMN), the materials contains Magnets, hence they are "ATTRACTIVE" to each other.
--For the Second case of Class1(ROW) to Class2(COLUMN), it is clear that as a magnet in class 1 is attracted to all the materials of class2, it is also named as "ATTRACTIVE".
--For the Third case of Class1 to Class3, it should be "Attractive".
--Similarly, for Class2 to Class2, "Not Attractive".
CLass2 to Class3, "Not Attractive".
and for the last one, Class 3 to class 3 itself, it should be "Not Attractive".

Hope I've answered your question appropriately.
Ok, I get what you are saying,but class 1 to 3 should not be attractive. They are not metals that provide magnetic forces. So then, how do I relate these to figuring out which bar in the HW problem belongs to which group. I just don't understand how to figure out the class from simple attraction and repulsion?
 
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