Chapter 14, Problem 5P

The current through a 6.8 k $\Omega$) resistor is as indicated. Find the sinusoidal expression for the voltage. In addition, sketch the u and i sinusoidal waveforms on the same axis.

$\begin{array}{l}\text{a}\text{. }0.1sin1000t\hfill \\ \text{b}\text{. }2\times {10}^{-3}sin(400t-{120}^{\circ })\hfill \end{array}$