05 Equipotential Computer Lab
EQUIPOTENTIAL SURFACES COMPUTER LAB ACTIVITY
Name:__ ________________________
Remember that an equipotential surface is the set of all points around a group of charges that are at the same potential. Hese surfaces allow us to calculate the amount of work needed to move a charge from one spot to another. The amount of work needed to move a charge q through a potential difference ΔV is given by:
W=qΔV
The purpose of today’s activity is to make you familiar with the shape and appearance of these equipotential surfaces and their replationship to the electric field.
1. After you have logged on to the computer, go to the resources page of the website and click the button labeled “Potential Surfaces and Electric Fields Activity” and save it to the desktop. Open the program from the desktop and maximize the screen. You will see an area for grabbing charges that can be placed in the area on the screen, a green box that allows you to change certain aspects of the area, and a movable tool that looks like this:
It is used to find the value of the potential at any point in space and plot the lines of equipotential in the area. The circle at the top changes color to reflect the relative magnitude and polarity of the potential at the point in the cross hairs. You will be using this tool to plot the potential lines.
2. Check the box in the green window labeled “Grid.” Notice that the major lines of the grid are at intervals of 0.5 meters. In the same window check the box labeled “Show E-Field.” Once a charge is placed in the test area, you will see arrows that represent the electric field due to the charge.
3. Place one of the positive charges in the center of the test area. Notice the electric field? Move the charge around a note what the field does. Answer the following:
a. How does the program show the direction of the electric field at any point?
The electric field points away from the positive charge.
b. How does the program show the magnitude of the
Name:__ ________________________
Remember that an equipotential surface is the set of all points around a group of charges that are at the same potential. Hese surfaces allow us to calculate the amount of work needed to move a charge from one spot to another. The amount of work needed to move a charge q through a potential difference ΔV is given by:
W=qΔV
The purpose of today’s activity is to make you familiar with the shape and appearance of these equipotential surfaces and their replationship to the electric field.
1. After you have logged on to the computer, go to the resources page of the website and click the button labeled “Potential Surfaces and Electric Fields Activity” and save it to the desktop. Open the program from the desktop and maximize the screen. You will see an area for grabbing charges that can be placed in the area on the screen, a green box that allows you to change certain aspects of the area, and a movable tool that looks like this:
It is used to find the value of the potential at any point in space and plot the lines of equipotential in the area. The circle at the top changes color to reflect the relative magnitude and polarity of the potential at the point in the cross hairs. You will be using this tool to plot the potential lines.
2. Check the box in the green window labeled “Grid.” Notice that the major lines of the grid are at intervals of 0.5 meters. In the same window check the box labeled “Show E-Field.” Once a charge is placed in the test area, you will see arrows that represent the electric field due to the charge.
3. Place one of the positive charges in the center of the test area. Notice the electric field? Move the charge around a note what the field does. Answer the following:
a. How does the program show the direction of the electric field at any point?
The electric field points away from the positive charge.
b. How does the program show the magnitude of the