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Electrode (surface area test)

What's the difference between one piece of metal and three pieces of metal in our cell. Does deflection change? Why? Created by Brit Cruise.

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• But it doesn't seem like that's increasing the surface area by that much. He's just adding two more coin widths, and those widths don't seem to drastically alter the surface area...
• Yeah! Thats the point. It proves that you dont need a drastically changed surface area to notice a change
• Why does he use pennies and nickles and not other coins?
• Throughout these videos, I have not understood what the "deflection" is.
• What is meant by deflection is:

how much the needle on the compass is pushed to the side.
• why does increase in surface area increases the mag. effect?
• Hello Siddhant,

In these videos Brit is performing experiments with a battery. By increasing the surface area of the plates he is increasing the "active surface" area. This allows more current to flow when he shorts out the battery through the coil of wire. With more current there is more magnetic field. With more magnetic field the deflection of the compass increases.

Regards,

APD
• When you say "surface area", do you mean the area which the electrodes touch the acid? But I feel like the area isn't really changing, the electrodes are only getting thicker, that's not a lot of changes. They are tripled up, some of the sides touched each other instead of touching the acid.
• Just wondering, are those pennies pure copper, or just copper plated? Also, would that make much of a difference?
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• can some one explain to me in detail ...how the compass and wires are connected??explanation in easy language will be appreciated.thanks:)
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• What about two pieces of metal? Is the deflection produced by two pieces simply going to be between the 1 and the 3 mark?
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• What kind of metal was that?
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• The silver one is zinc, the copper one is copper.
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• Why does the deflection change when one piece of metal and three pieces of metal are in the cell?
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