Question

1. The current through a 0.1-H coil is provided. Find the sinusoidal expression for the voltage across the coil. Sketch the v and i curves.

a. i = 10 sin 377t

b. i = 7 sin(377t - 70°)

2. The voltage across a 1-micro F capacitor is provided below. What is the sinusoidal expression for the current? Sketch the v and i curves.

v = 30 sin 400t

3. For the following pairs of voltages and currents, determine whether the element involved is a capacitor, an inductor, or a resistor, and determine the value of C, L, or R if sufficient data are provided

a. v = 100 sin(wt + 40°)

    i = 20 sin(wt + 40°)

b. v = 1000 sin(377t + 10°)

i = 5 sin(377t - 80°)

c. v = 500 sin(157t + 30°)

i = 1 sin(157t + 120°)

d. v = 50 cos(wt + 20°)

i = 5 sin(wt + 110°)

4. At what frequency will an inductor of 5 mH have the same reactance as a capacitor of 0.1 mF?

5. Sketch the following complex numbers in the complex plane and also convert them to rectangular to polar.

a. C = 3 + j 4

b. C = 0 + j 6

c. C =10 + j20

6. a. Find C1/C2 if C1= 15<10° and C2 = 2 <7°.

b. Find C1/C2 if C1= 8 <120° and C2 = 16 <-50°.

7. Find the input voltage of the circuit if v_a = 50 sin(377t+ 30°)

v_b = 30 sin(377t+ 60°) for f= 60 Hz and draw the waveforms where a and b passive elements are connected in series from a supply

Answer 1