A circuit consists of switches that open or close at t=0, resistances, dc sources, and a single energy storage element, either an inductance or a capacitance. We wish to solve for a current or a voltage x(t) as a function of time for t≥0. Write the general form for the solution. How is each unknown in the solution determined?

Q1

What is a capacitor and how do they work? What is it about capacitors that make them unique? What is the formula for one time constant? How many time constants does it take to fully charge a capacitor? Show illustrations. What other electronic component(s) are commonly found with a capacitor…especially in timing circuits? What types of capacitors are there? What are the formulas for series and parallel capacitors? If three 30 uF capacitors were connected in parallel what would the net capacity be? How about the net value if the capacitors in Q7 were connected in series? If you were to connect a 5K-ohm resistor in series as in Q7… what would the first time constant be? What about time to full charge? Describe the difference between AC (alternating current) and DC (direct current). Use illustrations. Why is voltage generated and distributed in AC? What type of circuit(s) would change AC to DC? How about DC to AC?

Att<0, a 360-nF capacitance is charged to an unknown voltage Vị. The capacitance is in parallel with a 36-k2 resistance. At t= 20 ms (millisecond), the voltage across the capacitance is 7 V. Determine the value of Vj.