An example is when u rub your pen on your hair hard that is friction
Answer: Permanent magnets consist of multiple "ferromagnetic materials" I think that might be the answer, there weren't really any choices for me to choose from.
<span>Reducing the distance between them. In theory, also increasing the mass; but you can't really change the mass of an object. However, you can compare the forces if you replace an object by a different object, which has a different mass.
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i hope this will work..
