Comments: Voltage, Current, Resistance, and Ohm's Law


Comments 10 comments

  • In the example with the tanks of the same amount of water except one has a larger pipe and the other has a smaller pipe, it says the voltage is the same in both both the amperage is lower in the one with the smaller pipe. Since current is the amount of electricity that flows past a given point in any given time, wouldn’t they both have the same current? Because although the smaller pipe would restrict the dimensions of water, wouldn’t the speed of the water in the smaller pipe increase which would in turn lead to its current being the same as the larger pipe?

  • ““1 Ohm” as the resistance between two points in a conductor where the application of 1 volt will push 1 ampere, or 6.241×1018 electrons.” – looks like this sentence has “per second” missing from the end.

  • At the beginning of text you said “The pressure at the end of the hose can represent voltage” . but in the ohm law section you said “The amount of water in the tank is defined as 1 volt ”. There is a difference between the two sentences. Please explaining more. thank you.

  • “We’ve chosen a resistor value that is high enough to keep the current through the LED below its maximum rating, but low enough that the current is sufficient to keep the LED nice and bright.”

    I think you need to reverse “high” and “low” there. It’s low enough that it won’t exceed the LED’s rating; it’s high enough to keep the LED bright.

    • Nope - the references (high and low) are in the correct positions. If the statement was, “We’ve chosen a CURRENT value…“ THEN you would need to swap them out. The current needs to be below the current rating - higher resistance means lower current, and lower resistance means higher current.

  • At first it says voltage is a difference in charge between two points. If it’s a difference in charge, why can’t it be measured in coulombs?

  • very good for me !!

  • Very interesting and much useful. Thank u… So much.

  • I suggest you guys make series of tutorial videos in the education channels for youngsters, and put them up on MOOC channels.

  • Thank you for the explanation. Very easy to understand.

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