Landon and Naomi are taking a physics class, and want to understand more about AC circuits. They know that an AC circuit consists of circuit elements and a power source that provides an alternating voltage V. This time-varying voltage from the source is described by v = Vmax sin(t), where Vmax is the maximum output voltage of the source, or the voltage amplitude. In a purely resistive AC circuit, the only circuit element type is a resistor. The friends want to get a clearer understanding about this circuit type, so they decide to use this simulation to explore. In this simulation a circuit consisting of a resistor of resistance R is connected to an AC source (yellow circle). Plots of the instantaneous current and instantaneous voltage across the resistor as functions of time are shown at the bottom, as well as a phasor diagram for the circuit. The friends can use the sliders to adjust the frequency, f, resistance, R, and maximum voltage, Vmax. They can click "start" to begin the animation, and "reset" to clear the graphs. They should note that lowercase symbols v and i indicate the instantaneous values of time-varying voltages and currents, respectively. Capital letters are