I’m working on a Physics question and need guidance to help me study.

Place position (

r
) values in meters in column A,

r

2

in column B,

k

r

2

in column C, and force (

F
) in column D. All of these values should be SI base units.

1.Place column labels in cell 1. Start placing values in cell 2.

2. In Column C, you are merely multiplying the constant

k
by the inverse of column B: =8.99E09*B2. Copy the formula down.

3. Plot

F

v

s

.

r

2

. Make sure you insert the correct graph! Label the graph for presentation. Afterwards, run a trendline by right-clicking the data. Chose power fit. Place the equation on the graph. Note the power it fit the curve with. Note: Do NOT run a LINEST or linear fit here!!!!!

4. Plot

F

v

s

.

k

r

2

. Is it linear? Label the graph for presentation. Run a LINEST by highlighting a 2 x 5 matrix starting around cell A15 or so. The theoretical slope should be the product of the two charges. So the slope should have units of

C

2

. Note the value of the slope and its uncertainty.

5. Do the same analysis in a different tab for the positive-negative data.

6. In the summary tab, address these questions:

• From the data (you) collected, does the power fit indeed illustrate the inverse-square Law? Explain. Note you have two scenarios of data you collected.
• We don’t know the charge on either sphere. But, we DO KNOW the product. What was the product of the two charges for both scenarios? Do these seem reasonable?
• Use the insert function to insert a small sphere and some arrows. Use these shapes to draw a force diagram of the approaching sphere at any position

r
for both scenarios. Assume for both scenarios that the stationary (source) charge is positive. Thus, for the second scenario, the approaching charge (the test charge) is negative. Label the drawing.

• Thinking about the above diagrams, what can we say about the rod attached to the approaching charge if the rod consists of “stiff” spring-like bonds for which atoms undergo small oscillations. What can we say, regarding both scenarios, about these springlike bonds when the charge is furthest away and closest to the source charge?
• List all random error in this lab that you can identify. Would these account for any discrepancies for the power fit?