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Resistance and potentiometers?
i am an A-level physics student who is failing to understand simple physics which is embarrasing to say the least but...
why is it that when a voltage is constant, when you decrease the resistance from a potentiometer, the multimeter across the potentiometer shows that the voltage increases?
I am struggling to understand this and it would be great if you could explain it.
The reason that i am confused is because ohms law V=IxR suggests that for resistance to decrease and voltage to increase current must decrease, how and why is this possible? Is this just in a simple circuit where you are only measuring the voltage across the power supply?
because say current is always 1, then when resistance decreases, so should voltage as you need to keep voltage/resistance 1, as that is the curent.
PLEASE USE OHMS LAW IN YOUR ANSWER TO EXPLAIN THIS THANKS
You need to get your head around the concept of voltage and current. Think of voltage as how hard it's pushing and current as the rate at which it's shifting. (Worry about what "it" is later!)
If you have a potentiometer with a constant current through it, the potential difference (think pressure difference) across the ends is also constant. If you put your volt meter at different points along the track, you will get readings from zero to the full potential difference.
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