Day 25 RL Circuits

Today, we go over RL (Resistance and Inductance) Circuits, to better understand exactly how induction works.

We took to an understanding exactly the importance of max peak and root-mean-square of both voltage and current (in AC, its the rms that matters, not the max peak). We find that the rms is 0.707, which is known as both the cos and sin of pi/4 or 45 degrees





The next following pictures are of the lab "RMS and AC Current and Voltage" where we find the rms vallues and max values given certain information

Part 1:
The first three pictures are of part one, in which we used the resistor of about 100 ohms, and measured multiple things from it.

Graph of the resistance in AC

Voltage vs current graph for resistance

Answering the questions

It is to note that in a resistance, the phase angle is in fact zero, that the resistance and the voltage are in phase with each other, which is shown by the voltage vs current graph, meaning the V=IR equation from Ohm's Law still applies in AC

Part 2

In part 2, we used a capacitor with indicated capacitance in order to find the relationship between voltage and current in a capacitor in AC

Capacitor graph (voltage vs current on the bottom)

Answering the questions of capacitance

Part two's experiment shows that the voltage and current in a capacitor in AC is not in phase with each other, and that the voltage is in fact ahead of the current by about 90 degrees

Part 3:

Part 3 focused on two parts, an inductor without an iron core and inductor with an iron core, to see if any difference arise as a result from it.

Solving the questions for inductors

The graph of the inductor with the iron core

Solving the questions of the inductor with the iron core

In part 3, I figured that since the experimental error of the inductor without the iron core showed to be over 10% (around 7x more) that I don't really need to see the graph, since the graph shows a lot of errors. However, with the iron core, we show that in the inductor, just like the capacitor, the voltage and the current are not in phase with each other, in fact in the inductor, the current leads the voltage (voltage lags the current) by 90 degrees, the complete opposite of the capacitor