## Investigating resistors

The aim of this experiment is to compare the results that were conducted from the experiment to the data found by calculation. From EM-5 that was aimed to investigate the effect of potential difference on current in a carbon resistor. EM-6 was to investigate how the addition of resistors in parallel or series affected the voltage and current in a circuit. EM-7 was to determine the total effective resistance of a combination of resistors in series and parallel.

The formula that was being used to calculate is I = where I is total current and Vs is potential difference and R is the total resistance in the system. The total resistance in series was forced by adding up all resistance in each resistor and using = in parallel. Another formula was Ir = where Ir is the current of one resistor and Vs is the potential difference and R is the resistor at one particular resistor. Furthermore, to find potential difference at one resistor used Vr = I. R where Vr is potential difference and I is total current and R is the resistance at 1 resistor.

There are three parts of procedures in this experiment. In EM-5, this as only one resistor was connected to the power supply of 3 v. Voltmeter and ammeter were used to find potential difference. The voltage of power supply was being changed to 6,9, and 12 v after 3v and resistors that have resistance also changed four more times. In EM-6 which was more complicated than EM-5 which to use three resistors that were set in parallel and series. First of all, three resistors were set in series and also used voltmeter and ampere meter to measure potential difference on the system.

On the other hand, in EM-7, we didn’t use series or parallel system either, but we combined them to set up the resistors. From the result that was gotten from this experiment and the results have been calculated using formula as stated before, there was slightly difference. This might be was caused by power loss and resistance of the wire. Other possibility was because the resistance of ampere meter was zero and that’s infinite as voltmeter which will never be gotten in the results.

The difficulties in this experiment were very usual in setting up the circuit especially in setting in parallel and combination circuit. We didn’t usual to do this kind of experiment. It was also making some mistake in conducting the experiment with a lot of variants or changes. In this experiment, we didn’t usual to read how many ohms in the resistor because we weren’t expert in this experiment. Overall, this experiment is success with the result of calculation. In the results which slightly difference that was because of power loss.

My suggestion is to use a small wire to make less chance to the power loss by reducing resistance from large area. The other suggestion is to be more careful and practice better in conducting this kind of experiment and learn again about how to set up the circuit and read each resistor. Those suggestions will improve the results and make more trials because faster and longer time. By doing this experiment, there should be an effect to our experience in doing all kind of electro. My suggestion may improve a lot if we will do this kind of experiment again.