PHYS 421 This lab will use the phet simulation "Charges and Potentials": https://phet.colorado.edu/sims/html/charges-and-potentials/latest/charges-and-potentials_en.html Experiment A. Collecting Data 1. Go to the simulation and check "Values" and "Grid". Check the distance scale at the bottom. Place two +1 nC charges separated by 4.00 m as shown in the figure. Electric Field Voltage Values Grid Equipotential D.OV 8.936 V - 2m 2 m O + voltmeter +1 nc -1 nc Sensors 2. You will use the voltmeter to measure the electric potential, V, along the x axis. You will place the sensor at various locations on the x axis for x 2 m and record the value of the electric potential. Use the number of data points for each region shown below. Region Data Points x 2m x = 2.4, 2.6, 2.8, 3.0, 3.5, 4.0 m Electric Potential Lab - PHYS 4213. Record your results in an EXCEL table. 4. Have EXCEL make a graph of V(vertical axis) vs. x (horizontal axis). Using EXCEL's graph as a guide, hand draw a graph. No numbers necessary just the correct shapes in all three regions. Be sure to locate the vertical asymptotes and draw them on the graph. You do not need to do a linear regression as we are not linearizing the graph. 5. Replace the +1 nC charge on the left with a -1 nC charge and repeat steps 2 - 4. Finding Points of Zero Electric Potential 6. In this part, you will use the simulation to nd locations where the electric potential is zero. Set up the charge system shown in the gure. For the +2 nC charge, place a l nC charge on top of another 1 nC charge. These charges are xed. Be sure to leave plenty of room to the right of the -l nC charge. Move the voltmeter along the x axis and nd two locations where the electric potential is zero. Exclude the x = :00 solutions. Move the voltmeter in all three regions. move voltmeter along x axis Write your value(s) of x here: 0.667 & 6.00 Electric Potential Lab - PHYS 421 2 7. You should have found two locations where = 0 in the previous step. One is between the charges and the other is to the right of the -1 nC charge. Let's solve this analytically. For the two figures shown below, find the value of x that makes the potential zero at P. Show your work below. Use V = ~ey ked for both charges and add them to get the net potential. First location: Second location: 2 m 2 m 2 m 2 m -1 nC K