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Question:

Why does a cow magnet go slower through a copper tube than a plastic tube?

Please help me!!! This is for my science class and i am so confused xS

Answer:

A magnet is not attracted to copper, so you might expect that it would not have any effect. But there is another property of magnets to keep in mind: a moving magnet produces an electric field. So, as the cow magnet moves through the copper tube, it creates an electric field that sets up small electric currents in the copper tube. These moving eddy currents in the copper have their own electric fields that work against the field of the magnet. These interacting fields are what slows down the cow magnet. The plastic tube is not affected by the moving magnetic field of the cow magnet, because plastic is not a conductor so no electric field is created in the plastic tube. We are most familiar with a moving magnet creating an electric current in a wire, the way a spinning magnet in an electric generator creates a flow of electricity, but a moving magnet will create an electric current in any conductor. It doesn't have to be a wire, and it doesn't have to be ferromagnetic. Hope this helps a bit.
A magnet gets attracted to metal (copper) Which means in a tube it will be attracted from all the directions This attraction holds the magnet in its current position But the the gravity attracts it down, while the tube holds it And resultantly the magnet tries to obey both the attraction (it tries to stay still and move down) which makes it fall slower than its fall in plastic tube where the plastic tube offers no attraction

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