Science Buddies: "Ask an Expert"

What temperature do magnets lose their magnetism? (Fahrenheit)
What affects the strength of magnets?
How do you make magnets stronger?
Do more magnets increase the strength of a magnetic field?

Hi,
This forum is intended for students, parents, and teachers working on K-12 science projects. If your question is related to a science project, please post some details such as your hypothesis, research question or experimental plan. If you are looking for help with homework or general science discussions there are other sites that are better suited to answering your questions.
Willey

What temperature do magnets lose their magnetism? (Fahrenheit)
What affects the strength of magnets?
How do you make magnets stronger?
Do more magnets increase the strength of a magnetic field?
What's the rarest magnet?
My science project is about magnets, I'm building a track that would propel a lego car, like a magnetic train track.

Hi rewd,
That's great! Best of luck with the track build. It sounds like fun! Just as a side suggestion, you may want to take a look at this project / resources on the site as well: https://www.sciencebuddies.org/science- ... ht#summary

Getting back to your questions, I have added my answers in blue below:

1. What temperature do magnets lose their magnetism? (Fahrenheit)
It depends on the type of magnet and its composition. Specifically, this temperature is called the "Curie Temperature" and is different for each material. Here's an example: (please look under curie temperature).https://en.wikipedia.org/wiki/Neodymium_magnet

2. What affects the strength of magnets?
I am assuming you are talking about permanent here - if so, it's most heavily influenced by the material property. (For temporary magnet like the ones used for maglev trains, those are electromagnet that are controlled via the amount of current flowing through them.)

3. How do you make magnets stronger?
Again, it depends on the base material and the composition of the alloy. (Typically, they are "graded") Here's an example: http://www.gaussboys.com/store/index.ph ... tings.html

4. Do more magnets increase the strength of a magnetic field?
If I am reading your question correctly, the answer is no, at least not on a per unit basis. It is possible to affect an object with multiple magnetic fields that results in a higher strength (this is called "superposition" and is the vector sum of the two field.)

5. What's the rarest magnet? I am sorry to say I don't know this one. I am going guess it's some kind of man-made rare-earth magnet that's in the higher portion of the periodic table. Usually, these type of material is not stable and breaks down quickly.

Hope that helps. Best of luck with your track!
Willey