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Discovery of Magnetism
The discovery of magnetism. What can we do with this invisible force?
Our ancestors noticed that certain rocks were attracted to each other. They also noticed that this force could be transferred onto certain metallic objects!
how would you know which way is north if you had no reference? Can the direction of stroke alone tell you this? Are you sure?
Does the direction which we stroke the needle determine the final orientation?
Can you use a magnet as a compass? How can you find North vs. South pole?
Making a Compass: does it matter if we stroke the needle with the North vs. South pole of the magnet? Why?
How to neutralize a compass using two needles. How could this help us later? Why does this work?
If we float two identically magnetized needles they will always orient themselves in the same way. Why?