DC Circuits exam with answers

DC Circuits exam with answers
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A few different circuit elements (batteries, resistors,
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capacitors, etc.) are connected in series. What do all of |\ |\ |\ |\ |\ |\ |\ |\ |\ |\



them have in common? - CORRECT ANSWERS ✔✔The
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current through each one is the same.
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Real wires are made from "ohmic" materials, meaning
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they have some amount of resistance and obey Ohm's
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law. If we want to account for this in a circuit diagram,
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how do we do so? - CORRECT ANSWERS ✔✔We include
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additional resistors representing the resistance of the wire
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and then treat the wires in the diagram as "ideal wires."
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Consider the circuit shown. When hooked up to a certain
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battery, there will be a current, I, moving to the right in
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the top wire (above resistor A). How would the current
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through resistor A compare to the current through the
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bottom section of wire between the points marked n and
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m? - CORRECT ANSWERS ✔✔The current through resistor
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A will be the same as the current through the bottom
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wire.


Current is defined (mathematically) by the equation I is
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equal to start fraction delta Q over delta t end fraction
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(for average current) or I is equal to start fraction dQ over
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, dt end fraction (for instantaneous current, using
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calculus). Using whichever definition you are comfortable
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with, when considering current in a wire, this can be
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stated (conceptually) as which of the following? -
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CORRECT ANSWERS ✔✔Current is the rate at which |\ |\ |\ |\ |\ |\ |\ |\



charge passes a certain place in the wire.
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Consider an electric current, I, travelling through a circuit
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when it encounters a junction, splits into two branches A
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and B, and later rejoins back together. What parameter(s)
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are involved in determining the fraction of the original
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current, I, that travels path B? - CORRECT ANSWERS
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✔✔The total equivalent resistance of both branches are
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the determining factors.
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Consider the following statement: "If you connect another
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resistor to an existing network of resistors, the total
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equivalent resistance will decrease." Is this true? - |\ |\ |\ |\ |\ |\ |\ |\



CORRECT ANSWERS ✔✔Yes, but only if the new resistor is |\ |\ |\ |\ |\ |\ |\ |\ |\ |\



connected in parallel with the existing network. |\ |\ |\ |\ |\ |\




Suppose you have a network of resistors with a total
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resistance R sub eq is equal to R sub I. If you hook up one |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\



more small resistor (compared to R sub i) in series with
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the original network, what would happen to the overall
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equivalent resistance? - CORRECT ANSWERS ✔✔R sub eq |\ |\ |\ |\ |\ |\ |\ |\



will increase a small amount.
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