# P0 - Characterizing An Unknown Component Manually

Tyler Nolan

Professor Spicklemire

Physics 230 - Labratory Instrumentation

January 21st, 2021

## Abstract

This lab measured the resistance of an unknown component by collecting data on the current and voltage of the circut. In the end we were able to verify the resistance of the unknown component in the LTspice and TinkerCAD as 1000Ω and 702.6Ω respectively.

## Description

The purpose of this lab was to begin familiarizing ourselves with some of the programs used in this course such as LTspice, TinkerCAD, and DeepNote. We constructed a voltage divider on both LTspice and TinkerCAD to find the resitane of an unknown component. This voltage divider works by dividing the voltage from a power source through a resistor. By finding the voltage drop across the component and knowing the current we can find the resistance by V/I = R. When we graph V vs. I we can find the resistance as the slope of the graph. As the voltage was increased incrimentally the voltage drop and the current were recorded. Then the results were graphed as described previously.

## Schematics

LTspice Schematic:

In this schematic "R2" is acting as our "unknown component. Even though we know that it has a resistance of 1kΩ we can still preform the same simulation and we should find that the math brings us to a result of 1kΩ just the same.

TinkerCAD schematic:

In this schematic a photoresistor is used as the unknown component. We can use the voltage drop and current measurements to figure out its true resistance value.

## Data

The data collected from the LTspice simulation is shown below.

The data from the TinkerCAD simulation is shown below.

## Results

If we graph the voltage drops vs. the current for either of the simulations we can find the resistance of the component in question.

The graph for the LTspice simulation is shown below.

As previously stated, the resistance of the unknown component is equal to the slope of the line which is...

This makes sense because we used a 1kΩ resistor as our "unknown" resistance in the LTspice experiment.

The resultant graph for the TinkerCAD simulaton is as follows.

Once again we can find the resistance of the photoresistor by finding the slope of the graph which is...

In this instance we cannot verify the accuracy of this value since TinkerCAD does not show the resistance of the photoresistor but it would make sense that the value is between 0 an 1000Ω and that it is above 500 since the slider to adjust the "light" the photoresistor was recieving was over halfway to te right when the measurements were made.

## Conclusion

This lab accomplished all of its goals very well. It was a great introduction to LTspice, TinkerCAD, and DeepNote. We were able to find the resistance of the unknown component in both the LTspice and TinkerCAD simulations as 1000Ω and 702.6Ω respectively.