Lab Section: ______
Name: ______________________________
Lab Instructor: ___________________
Instructor’s Signature:
__________________
P2207 Lab Working Notes
Questions 2-1
Cornell University, Fall 2010
Lab 2 Data
A. Numerical Differentiation
1. From the Excel spreadsheet
Ball
:
Note: You will only be able to enter your data into the bottom two cells of the "Value" column
below AFTER you have completed the data fitting proceedure described in the boxed text on
p.2-2 in the Lab Manual.
Table Column
Cell Address
Excel Formula
Formula with
Conventional Symbols
Value
(s)
D12
=B12-B11
0.02
D13
=B13-B12
0.02
(m)
E12
=C12-C11
0.04
E13
=C13-C12
0.035
(m/s)
F12
=E12/D12
2
F13
=E13/D13
1.75
G12
=$G$8+$G$7*B12
1.96
G13
=$G$8+$G$7*B13
1.77
What order of magnitude (i.e., power of ten) for the acceleration
do the data-derived values in
the above table suggest?
Is that reasonable for free fall?
.
That’s roughly
, so it’s a reasonable value for a falling object.
2. Record your value of
from the straight-line fit to the
data, including a
±
error
estimate based on how consistently you and your partners could arrive at a straight-line fit:
The acceleration
is about
.
Variations may be within about
, indicating that the error in the fitting procedure is roughly
.
Print out a copy of your spreadsheet from Excel (one for each student) and attach it to this
yellow sheet.

This
** preview**
has intentionally

**sections.**

*blurred***to view the full version.**

*Sign up*
P2207 Lab Working Notes
Questions 2-2
Cornell University, Fall 2010
B. Play Ball: Experimental Data from a Bouncing Basketball and Beachball
To get started, double-click on the icon "Bounce".
Logger Pro will open, showing a layout of
three graphs:
x(t), v(t)
and
a(t).
Before
you aquire any data, you must first enter today's room temperature into the data
acquisition program (Logger Pro):
Select menu item "Experiment... Set Up Sensors > Lab Pro: 1".
A window called "LabPro: 1"
will open.
Click on the "DIG/SONIC 1 Motion Detector" icon and select "Set Temperature".
Enter today's
room temperature (use the thermometer on the wall) and click "OK".
Close the "LabPro: 1"
window.
Why did you need to do this?
Because you are measuring position using ultrasound waves. The
speed of sound depends on temperature, and the computer needs the correct speed-of-sound to
use in its calculation of position.

This is the end of the preview.
Sign up
to
access the rest of the document.