E84 Midterm Exam 1

Instructions

• Take home, open notes, feel free to use a calculator, but not any software package such as Multisim.
• Mark your start and end times. Don't spend more than 3 hours. Due on Monday in class.
• Compare your print-out of the exam with the online version to make sure your hard copy is complete.
• Mark your name and question number clearly on top of each page. Indicate the total number of pages submitted.
• When solving a problem, list all the steps. In each step, indicate concisely what you are doing in English, then show the calculation and the result of for the step. Box the final answer. A final answer, even if correct, without evidence of the steps leading to it will receive ZERO credit.

1. Problem 1. (30 pts)

   Find the two currents labeled as $I_a$ and $I_b$ in the figure.

   

2. Problem 2. (30 points)

   Find the voltage $V$ across the 2$\Omega$ resistor (with assumed polarity shown), and the current $I$ through the 1$V$ voltage source (with assumed direction shown).

   

3. Problem 3. (40 pts)

   The following two parts of the problem are independent, each worth 20 pts.

   • Find the resistance $R$ so that the voltage across the resistor is 1V.
   • Find the resistance $R$ so that the current through the resistor is 0.2A.