In the circuit figure the emf, epsilon, is 9V, R1 is 2 ohms, and R2 is 6 ohms. What is the magnitude of the current that passes through the wire that is marked A?
To solve this I know you need the circuit figure so go to this website
http://www.hippocampus.org/course_locator?course=AP Physics C II&lesson=31&topic=4&width=800&height=68…
just copy and paste in your browser and once you go to the page wait for the interactive video to start and then you should fast forward to the problem that reads like the the question I just posted. They give you the answer if you click on the diffrent answer choices until you get the correct one, but what I want to know is how to do it I don't get it no matter how hard I try I've been on that same problem for hours and I can't solve it. Please someone help me I would think its a mistake or something, but I probably wrong so please can someone solve and then explain this to me. Don't sent me to another website of tell me to just see the video because I have already seen it like four times, and I could do everything except that problem.
Remeber to be as clear as possible when explaining how to do this problem don't just give me an answer. I need a good explanation better then what the website gives you.
To solve this I know you need the circuit figure so go to this website
http://www.hippocampus.org/course_locator?course=AP Physics C II&lesson=31&topic=4&width=800&height=68…
just copy and paste in your browser and once you go to the page wait for the interactive video to start and then you should fast forward to the problem that reads like the the question I just posted. They give you the answer if you click on the diffrent answer choices until you get the correct one, but what I want to know is how to do it I don't get it no matter how hard I try I've been on that same problem for hours and I can't solve it. Please someone help me I would think its a mistake or something, but I probably wrong so please can someone solve and then explain this to me. Don't sent me to another website of tell me to just see the video because I have already seen it like four times, and I could do everything except that problem.
Remeber to be as clear as possible when explaining how to do this problem don't just give me an answer. I need a good explanation better then what the website gives you.
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I can't do it either! I looked at the worked solution and that has a fault of logic - it claims IB = IC. This cannot be true or the voltages across (identical) resistors B and C would then be equal; That would mean the voltages across the top 2 resistors would both be equal too. No current would then flow through A.
Edit. I have a theory. The official solution is nonsense. The presence of a zero resistance ammeter is a short circuit. The circuit is equivalent to the top 2 resistors (6ohm and 2 ohm) in parallel (total = 1.5 ohm). and the bottom 2 resistors (each 2 ohms) in parallel (total 1ohm). The 2 parallel resistors are in series - total circuit resistance = 2.5ohms. There is NO current through the ammeter - as there is no potential difference. The question would be very different if the ammeter had some resistance - but it doesn't. Well that's my theory anyway.
Edit. I have a theory. The official solution is nonsense. The presence of a zero resistance ammeter is a short circuit. The circuit is equivalent to the top 2 resistors (6ohm and 2 ohm) in parallel (total = 1.5 ohm). and the bottom 2 resistors (each 2 ohms) in parallel (total 1ohm). The 2 parallel resistors are in series - total circuit resistance = 2.5ohms. There is NO current through the ammeter - as there is no potential difference. The question would be very different if the ammeter had some resistance - but it doesn't. Well that's my theory anyway.
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The total current won't go through A because there are some other zero resistance routes, e.g. directly from top right to bottom right resistor for the right hand side current.
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