You will construct a simple pendulum with enough string so that you can vary the length at least 6 times. You will need a digital timer such as your phone. Excel spreadsheet format (starting from A1 and through F1 for column labels): Length Trial 1 Trial 2 Average Period Period-squared 1.Look over your experimental design. Make sure you can release the bob at an angle less than 10 degrees and at the SAME POINT each time. 2.Measure the length of the string from where it is tied and go down to the center of gravity of the bob. Record all the different lengths that you use starting in second cell of column A of your Excel Spreadsheet (Record in meters). 3.(IMPORTANT SPECIFIC INSTRUCTION FOR THIS LAB). For a given length, simultaneously release (ALWAYS from the same point) the bob and start the timer. Let it oscillate three complete oscillations. Place the amount of time it took to complete these three oscillations starting in the second cell of column B (cell B2). Repeat this timing event for this length and place that value in column C. Finally, in column D in cell 2, type (without the quotes), "=AVERAGE(B2:C2)". So, you are timing the time it takes for three oscillations twice so you can take the average of these as your final value. 5.Repeat the process for at least 5 other lengths; placing the time for three oscillations (trial one) in column B and (trial 2) in column C. Go to cell D2 again and copy the formula down by clicking on the bottom-right corner and dragging it down. Now you have average values for three oscillation times down to cell D7 (a total of six different lengths). 6.In cell E2, type, "=(D2)/3". This will give the time for ONE oscillation. Recall the formula for the period of a simple pendulum: T=2Lg T = 2 L g Let us now linearize this: T2=42gL T 2 = 4 2 g L Accordingly, YT2 Y T 2 XL X L slope = 42g 4 2 g 7.In cell F2, type the equation "=E2^2". Copy the formula down. This is your "Y" column. Here you are simply squaring the period. 8. Plot Y vs. X by clicking on column A (hold "shift") and click column F. Just highlight the values in column A, hit shift, and then highlight the values in column F if it makes it easier. Insert graph and chose the appropriate xy-scatter plot showing your data. Label the graph. 9. Highlight a 2 x 5 matrix as you have done before. Run a LINEST with column F being the y-values, column A being the x-values. Click TRUE,TRUE naturally. 10. Call 42g 4 2 g . ideal=4.02s2m i d e a l = 4.02 s 2 m . Report your value AND its uncertainty