True-false questions are worth 2 points each, three-choice multiple choice questions are worth 3 points each, five-choice multiple choice questions are worth 6 points each. The maximum possible score is 92. The exam period was 75 minutes; the mean score was 55.1 the median was 55. Click here to see page1 page2 page3 of the formula sheet that came with the exam.

Some helpful information: • A reminder about prefixes: p (pico) = 10^{-12}; n (nano) = 10^{-9}; μ (micro) = 10^{-6}; m (milli) = 10^{-3}; k (kilo) = 10^{+3}; M or Meg (mega) = 10^{+6}; G or Gig (giga) = 10^{+9}.

(T) True (F) False

(a) When the bulbs are in parallel, they glow more dimly, but for a longer time than the series. (b) When the bulbs are in series, they glow dimly and extinguish more quickly than when in parallel. (c) In each trial, the same amount of energy is dissipated by the bulbs.

(a) It stays the same because the battery has been removed. (b) It increases because the charge in the circuit increases. (c) It increases because the charge on the first capacitor decreases.

A positive charge Q_{1}= +4 μC is located on the x-axis at x = -4 m. A negative charge Q_{2} = -12 μC is at the origin (x = 0, y = 0).

What is the y-component of the electric field at y = 5 on the y-axis?

(a) 5000 N/C (b) -3400 N/C (c) -3600 N/C (d) -5000 N/C (e) -16000 N/C

(a) x = -3 m (b) x = -2 m (c) x = -1 m

(a) +0.03 J (b) -0.03 J (c) -0.14 J (d) -0.24 J (e) -0.48 J

Three charges (Q_{1} = Q_{2} = +4 μC, Q_{3} = +6 μC) are located at the vertices of an equilateral triangle of side 70 cm.

What is the magnitude of the force exerted by Q_{1} and Q_{2} on Q_{3}?

(a) 0.31 N (b) 0.44 N (c) 0.53 N (d) 0.76 N (e) 0.88 N

(a) 0.82 J (b) 1.18 J (c) 820 J (d) 180000 J (e) 257000 J

(a) In this case, the work done to assemble the charges would be the same as in the previous question. (b) In this case, the work done to assemble the charges would be the negative of the previous answer.

In the circuit shown, the battery voltage ε = 20 volts, and the capacitors C_{1} = 70 μF, C_{2} = 30 μF, C_{3} = 21 μF, and C_{4} = 28 μF.

Calculate the total capacitance of this network of capacitors.

(a) 33 μF (b) 49 μF (c) 81 μF (d) 100 μF (e) 149 μF

(a) 2.94 mJ (b) 4.2 mJ (c) 12 mJ

V_{with} - V_{without}

(a) -1.9 V (b) -0.95 V (c) 0 (d) 0.95 V (e) 1.9 V

(a) The dielectric in C_{4} has no effect on the charge stored in C_{1}. (b) The dielectric in C_{4} reduced the charge stored in C_{1}. (c) The dielectric in C_{4} increased the charge stored in C_{1}.

In this circuit, you are given R_{1} = 10 Ω, R_{2} = 36 Ω, R_{3} = 9 Ω, R_{4} = 36 Ω and R_{5} = 10 Ω. Note the arrows defining the currents I_{2} and I_{4} through resistors through R_{2} and R_{4, }respectively. You are not told the battery voltage.

True or false: resistors R_{2} and R_{4} are in parallel.

(a) 4.48 Ω (b) 40 Ω (c) 60 Ω (d) 81 Ω (e) 101 Ω

(a) 60 mA (b) 80 mA (c) 100 mA (d) 125 mA (e) 167 mA

The circuit shown contains a capacitor which is initially uncharged.

Close switch S at t = 0. What current initially flows into the capacitor?

(a) 0.133 A (b) 0.2 A (c) 0.4 A

(a) 2.4 μC (b) 4.8 μC (c) 8.8 μC (d) 12.1 μC (e) 13.2 μC

(a) 0 (b) 0.118 A (c) 0.139 A (d) 0.177 A (e) 0.2 A

Is the equation I_{1} + I_{2} + I_{3} = 0 true or false?