Diodes

Diodes are important as they only allow current to flow in one direction and are used in places like rectifiers on an alternator.
The first test we did was to measure the resistance of the diode using the 2k setting on the ohm meter. The meter read infinity because the ohm meter does not put out enough voltage to break through the bindery layer of the diode. We then tested the diode using the diode test position on the multimeter. We got a reading of infinity from the cathode to anode position, and .54v from the anode to cathode position which means it it needs .54v to break through the diode.
Next we set up a small circuit using a 12v power supply, a 1kΩ resistor, and a diode. The resistor had a voltage drop of 12.71v, and the diode had a voltage drop of .66v. The diode should not have a big voltage drop because it is not a consumer. The voltage drops add to 13.37v and the available supply voltage was 13.37v. The current flow at the diode measured .013A.
In a series circuit, the voltage drops of each consumer should add to the total supply voltage.
The next test was the same, except we used a bigger resistor, a 9.89kΩ resistor.
Voltage drop across the resistor didnt change a huge amount, but was slightly bigger at 12.81v and .56v across the diode. The current flow however was alot lower at .001A
Because we have a bigger resistor, there was a higher voltage drop and less current.
In the next part of the test we used a light emmiting diode, instead of a normal diode and a 1kΩ resistor. Using the diode tester, we found the LED needs 1.95v to break through it. In doing this we found that the voltage drop of a LED is higher than that of a normal diode.
We found the voltage drop of the resistor was 9.04v and the voltage drop of the LED was 4.3v. The sum of the voltage drops is 13.34v and the available supply voltage was 13.35v. The current flow of the LED was .01A.
In the diode circuit, the diode doesn't use much voltage, therefore the resistor uses more. In the LED circuit, the LED uses mor voltage than the diode, so the resistor doesn't use as much.