- #1
BeautifulLight
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This thread will concern the workings of potentiometers, but I could use some help tackling something first. I will explain in my next post!
Assume I have shorted out a battery with some resistor.
I always thought that if you had a high enough resistor value, you could stop current from flowing. How? The battery has some potential difference in volts. I see this as an attractive force (well, when given a conducting path). So let's take this attractive force in volts, and convert it to joules. So let's say I have an attractive force of 10 Joules. Now onto the resistor. I see this as the inverse of the battery's attractive force, so it's a repelling force. So imagine I start swapping out that resistor with ones of higher and higher values. When the resistor reaches a repelling force that is equal to the battery's attractive force (so at 10 Joules), then current should cease to flow. It's analogous to taking two 9V batteries and wiring one's negative to the others positive and vise versa.
I tried keeping that as elementary as possible so you can see where I'm coming from. I know it's incorrect, but I can't help to think of it that way. Why?
If you were to theoretically short out a battery with a resistor value of 0 ohms (use your imagination), you could figure out the maximum current value that battery can supply. Just use the battery's internal resistance. But what happens when you go the other way with it? What is the least current a battery can supply? If I have a 1V battery, I can keep plugging in higher and higher resistor values -I'll just keep getting a smaller and smaller fraction for the current.
Is there a limit?
Assume I have shorted out a battery with some resistor.
I always thought that if you had a high enough resistor value, you could stop current from flowing. How? The battery has some potential difference in volts. I see this as an attractive force (well, when given a conducting path). So let's take this attractive force in volts, and convert it to joules. So let's say I have an attractive force of 10 Joules. Now onto the resistor. I see this as the inverse of the battery's attractive force, so it's a repelling force. So imagine I start swapping out that resistor with ones of higher and higher values. When the resistor reaches a repelling force that is equal to the battery's attractive force (so at 10 Joules), then current should cease to flow. It's analogous to taking two 9V batteries and wiring one's negative to the others positive and vise versa.
I tried keeping that as elementary as possible so you can see where I'm coming from. I know it's incorrect, but I can't help to think of it that way. Why?
If you were to theoretically short out a battery with a resistor value of 0 ohms (use your imagination), you could figure out the maximum current value that battery can supply. Just use the battery's internal resistance. But what happens when you go the other way with it? What is the least current a battery can supply? If I have a 1V battery, I can keep plugging in higher and higher resistor values -I'll just keep getting a smaller and smaller fraction for the current.
Is there a limit?