# Lab Report On Ohm 's Law

1224 WordsMar 29, 20175 Pages
Lab Report 3 Ohm’s Law Physics 262-003 Author: A. Coughran Lab Partners: E. Ortiz, H. Barham Date: 3/29/17 Lab Report 3 A. Coughran 3/29/17 Objective: The objective in Lab 3 is to experiment with different voltage and current values for series and parallel circuits under given circumstances. Theory: For both series and parallel circuits, resistors have an effect on the voltage and current going through the circuit without changing their own values. Equation 1 shows how the resistance value is related to the current and voltage in the circuit. V=iR Equation 1 V represents the voltage in the circuit, i represents the current in the circuit, and R represents the resistance value in the…show more content…
Procedure A: Current and Voltage for a Single Resistor The power supply was set up and the multimeter was set to the 2A DC ammeter setting. The 33 ohm resistor was placed in series with the voltmeter and the ammeter. A sketch of the circuit is shown below. The power supply was turned on and 0.5 Watts were passed through the circuit with the ammeter and voltmeter initially turned off as to prevent any damage. The maximum voltage was calculated to be V_max=4.062 V by using Equation 3 and the current and voltage readings, as well as a 33 ohm resistance value. Next, a linear graph of voltage vs. current was collected by turning the voltage between 0.25 V and 0.50 V, then increasing it to slowly approach the maximum voltage value. By doing this, current values were collected for several voltage intervals. All values for this procedure were recorded in a table and plot and are shown in the data section. A linear regression of the voltage vs. current data was then taken to find the experimental resistance value. Procedure B: Current and Voltage for Series Resistors The same steps from Procedure A were repeated, but a 100 ohm resistor and a 33 ohm resistor were set up in a series circuit together (shown below). The peak voltage was slightly higher for this procedure, so the starting