Physics 2 · Unit 3 · Paper 1

Electric Circuits unit test

A test on this unit alone, marked as a percentage and a letter grade — for the test your class is actually sitting, rather than for May. Answer everything, then submit once: seeing the answer to question 3 before attempting question 4 makes the final percentage meaningless.

Paper 1 Paper 2 Paper 3

Each paper is built from this unit’s 24 terms and is the same for everyone, so a teacher can assign “Unit 3, Paper 1” and every student sits the identical test. Multiple choice is marked objectively; the written sections you mark yourself against the model answer and rubric.

Suggested time 37 min 34 points0/17 attempted

Reading a circuit diagram

Kirchhoff sign conventions

Resistance and resistivity

Internal resistance and terminal voltage

Electrical power

Current

Parallel resistors

Dielectric

Ohm's law

Energy dissipated during capacitor charging

Series vs parallel capacitor voltage

Capacitor behavior at t = 0 and t = ∞

Short answer 1. Define or explain: Capacitor charging graph

3 pts

Short answer 2. Define or explain: Series resistors

3 pts

Short answer 3. Define or explain: Kirchhoff's loop rule

3 pts

Short answer 4. Define or explain: Kirchhoff's junction rule

3 pts

Free response

10 pts

An ideal 12 V battery is connected in series with R₁ = 4.0 Ω. That resistor feeds a parallel combination of R₂ = 6.0 Ω and R₃ = 3.0 Ω.

Calculate the equivalent resistance of the circuit and the current delivered by the battery.

Calculate the potential difference across the parallel combination and the current in each of R₂ and R₃.

Calculate the power dissipated in R₁ and verify that the total power dissipated equals the power delivered by the battery.

An initially uncharged 100 μF capacitor is now connected in parallel with R₃. Determine the current delivered by the battery immediately after the connection is made, and a long time later.

Calculate the final charge on the capacitor and the energy stored in it.