1stproject
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Joined: Sun Apr 10, 2016 8:07 pm
Occupation: Parent

Polarity of nails

Postby 1stproject » Sun Apr 10, 2016 8:09 pm

I was doing a project about the gender frustration. We tried to put paper clips of the nails to see if they would stick, but some did and some didn't. What's the reason that some didn't? Even for those that worked, the magnetic field was very weak to create any pattern. How can I fix these problems?

williamcolocho
Former Expert
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Joined: Sat Dec 13, 2003 10:02 am

Re: Polarity of nails

Postby williamcolocho » Tue May 03, 2016 9:09 pm

I just read the description of the project, so I'm not really an expert on it. The experiment setup is designed not to work. i.e. it's impossible to recreate the pattern and not all the paper clips will stick. This is what I think is going on: as the paper clips touch different nails, different electric loops are created, these loops induce magnetism that affect other paper clips. By changing the polarity of the setup as the test subject changes the configuration, you are making some magnetic fields become attractive and then repulsive. Attractive loops will stick, repulsive ones will not. Every time a loop change happens or the polarity changes it's a new configuration.

Hope this makes sense. The point is that each local electric loop makes a local magnet that may or may not align with it's neighbours.

1stproject
Posts: 2
Joined: Sun Apr 10, 2016 8:07 pm
Occupation: Parent

Re: Polarity of nails

Postby 1stproject » Wed May 04, 2016 6:36 am

I have experienced the difficulty of making paper clips sticking to to electrically magnified nails when I helped my daughter's project. I think one instruction in the procedure is wrong. It says connecting the battery for each nail the same way. That means the nail heads of 16 nails can be all N or all S, depending on electric current direction. Then, if attach a paper clip onto two nail heads with same polarity, the paper clip does not stay on the nails if crossing two heads securely because same polarity repulses each other. However, clip can stick to one nail fine. So, I changed the battery direction for neighboring nails for making one head N and the other head S. Then the clip stays nicely bridging two nails. After applying double pole and double throw switch, the paper clip drops successfully. So, it works.


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