# Electronics: Totally Legitimate Science

385

9

## Introduction: Electronics: Totally Legitimate Science

Experiments with electronics 12th of July 2016

## Step 1: Ohm's Law.

Ohm's Law states that electric current is proportional to voltage and inversely proportional to resistance. To prove this we must; change the voltage, resistance, and Current and record results.

## Step 2: We Only Had an Ammeter.

We only had an ammeter, so we couldn't measure voltage. Thus we had to change the resistance and record the effect on the current. With the same voltage, we could expect the current to proportionally change with added resistance. Eg; reduce resistance by 10x, you can expect current to increase by 10x. We had a voltage of 3 volts, and a resistance of 10 kilohms; the current was 0.3 milliamps. We then increased the the resistance to 100 kilohms, the current changed to 0.03 milliamps.

## Step 3: Kirchoff's Voltage Law

This Law states that “in any closed loop network, the total voltage around the loop is equal to the sum of all the voltage drops within the same loop". We had to prove this. But it is difficult without a Voltmeter, or specific resistors. So here's the theory; We would measure the Voltage difference after multiple resistors (in series) , and each one would drop the voltage a proportional amount. and the total voltage drop would be equal to the voltage from the power source. Source: http://www.allaboutcircuits.com/textbook/direct-current/chpt-6/kirchhoffs-voltage-law-kvl/

## Step 4: Other Information That We Learned

Electricity passes takes the path of least resistance. This can be demonstrated by putting a motor in parallel to a push switch. With the motor being the only thing that closes the circuit, the motor activates, with the switch open, the motor does not activate, because that requires more effort, or more resistance.

## Step 5: Then We Built a Speaker.

this was our first attempt at something functional. we connected a phone to a circuit in the attempts to make the speaker activate. We figured we needed an amplifier, a connector, a speaker, and batteries. It didn't work.

## Step 6: But Then We Made It Work

We looked at this tutorial, and then followed it. It worked, it was terrible, but it worked. (Picture credit: Enric Perich)