Compound Direct Current (DC) Circuits AP Physics 2 FRQ – Exam Style Questions etc.
Compound Direct Current (DC) Circuits AP Physics 2 FRQ
Unit 11: Electric Circuits
Weightage : 15–18%
Exam Style Practice Questions , Compound Direct Current (DC) Circuits AP Physics 2 FRQ
Question: (7 points, suggested time 13 minutes)
A circuit contains a battery and four identical resistors arranged as shown in the diagram above.
(a) Rank the magnitude of the potential difference across each resistor from greatest to least. If any resistors have potential differences with the same magnitude, state that explicitly. Briefly explain your reasoning.
Ranking:
Brief explanation:
Resistor B is now removed from the circuit, and there is no connection between the wires that were attached to it. The new circuit diagram is shown below.
(b) When resistor B is removed, does the current through resistor A increase, decrease, or remain the same?
________Increase __________Decrease ___________Remain the same
Briefly explain your reasoning.
(c) When resistor B is removed, does the current through resistor C increase, decrease, or remain the same?
_________ Increase ________ Decrease ___________ Remain the same
Briefly explain your reasoning.
Answer/Explanation
Ans:
(a)
A has same potential difference as D. B \(\frac{1}{3}\) , C are less than A \(\frac{1}{3}\) , D but equal to each other.
Brief explanation:
Since A and D are identical resists with the same amount of current through both of them, they have the same potential difference (V – IR) B and C are in a parallel structure so current gets split between them, making each of their potential differences v = \(\frac{1}{z}\) IR
(b)
X Decrease
Current (I) is \(\frac{potential difference}{resistance}\) (I = \(\frac{V}{R}\) )
When B and C where in a parallel circuit, B \(\frac{1}{3}\) C’s combined resistance were less than either one of them. Therefore, is A, C, and D are all in a series there will be more resistance which equals less current.
(c)
X Increase
When B \(\frac{1}{3}\), C where in a parallel circuit, current was split evenly between them. Current is the same for all resisters in a serves, and since the removal of be creates a series circuit including C, C will get all of the current within the circuit.