The force between point electric charges can be determined using Coulomb’s law. Coulomb’s law states that the force between two point charges is inversely proportional to the square of the distance
between the charges and directly proportional to the product of the charges.
In this investigation, you will examine the nature of forces between charges.
Purpose:
Part 1: To examine the force between charges at varying distances from each other
Part 2: To investigate the force between charges at different distances or different charges at one distance
Equipment and Materials
Ruler
Calculator
Computer with Internet access
Computer with graphing software
Graph paper
Requirement:
Step1: Graph and Simulation. Table 1 shows data for the force between two equally charged particles separated by a distance. Using the data in Table1, graph force versus 1/r^2 on the computer.
Draw a line of best fit for the plotted data, and determine the slope of the line. Teacher will use a checklist to observe the procedure of your graph& simulation. During this step, teacher may ask
you some extending questions involving your procedure. Please be note that the answer that you give may also affect your total mark for the performance.
Step 2: Analysis. Hand in an answer sheet in class, the following part should be included:
Based on the slope of the line you created, determine the charge of each particle (D2.3 half)(20points) (k/u,t)
Explain whether or not your results of simulation are consistent with Coulomb’s law. If there is any discrepancy, explain the possible reasons for it. (D2.5 A1.8)(40 points) (k/u,t,c,a)
The procedure of your calculation and printed graph (D2.1A1.13)(40 points) (k/u,t,c,a)
Table 1
r(m) FE(N)
0.1*10-6 9.21*10-14
0.2*10-6 2.30*10-14
0.3*10-6 1.02*10-14
0.4*10-6 5.75*10-15
0.5*10-6 3.68*10-15
0.6*10-6 2.56*10-15
0.7*10-6 1.88*10-15
0.8*10-6 1.44*10-15
0.9*10-6 1.14*10-15
1.0*10-6 9.21*10-16
1.1*10-6 7.61*10-16
1.2*10-6 6.39*10-16
1.3*10-6 5.45*10-16
1.4*10-6 4.70*10-16
1.5*10-6 4.09*10-16
1.6*10-6 3.60*10-16
1.7*10-6 3.19*10-16
1.8*10-6 2.84*10-16