Lab and Report for : Sample Lab Report
What must be contained in the Lab Report:
1. Title
 descriptive
2. Introduction/ Objectives Section
 what principles will be demonstrated by this lab
 why is this a good method to demonstrate these principles
 how will the principles be demonstrated by this lab
 state ALL hypotheses
 background research with citations in correct APA style*
3. Materials list
 include types and amounts of chemicals
 include ALL types and sizes of equipment used
4. Safety precautions
5. Methods Section
 Numbered, step-by-step instructions
 Amounts to be used
 Data to be recorded and when it is to be recorded
 Clean up instructions
6. Results Section
 data tables
 graphs, charts (if any)
 sample calculations (if any)
7. Discussion Section
 State if hypotheses were supported or refuted
 Cite data to backup your claim about hypotheses
8. Reference Section
 In correct APA style*
 One for each citation given in the Introduction
* http://owl.english.purdue.edu/owl/resource/560/01/
REPORTS MUST BE TYPED
DATA TABLES/ GRAPHS MUST BE:
 Computer generated , or
 Drawn with straight edges (protractor, etc.)
ALLOW 1 CLASS PERIOD TO COLLECT DATA*
NO MORE THAN 2 TO A GROUP
*If your lab partner is absent the day of the data gathering but you were not absent you must continue
on your own and your lab report is still due on the pre-assigned day. If you are absent, you must
come in on your own time to gather your data. You may NOT use your lab partner’s data. Your
report is due the day after you finish gathering the data. Data MUST BE gathered within 5 days of
your absence or this opportunity is lost and you will receive a zero for the assignment.
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Lab and Report for : Sample Lab Report
Name: Terry Testtube
Lab Partners: Excellent helper #1
Due Date: 8/27/1999
Excellent helper #2
SAMPLE LAB REPORT
Effect of Gravity on Rate of Fall
Introduction:
During this laboratory exercise we attempted to show that the force of gravity has the same effect on all falling bodies near the
earth. We intended to show this by dropping several objects in normal atmospheric conditions, and in a vacuum chamber.
Galileo discovered that gravity was a force that caused all bodies to fall and he further showed that gravity caused the same
rate of fall on all bodies. (“Falling Bodies”, 2012) The motion of any moving object is described by Newton’s Second Law of
Motion, Force = mass x acceleration. (“Free Falling Objects:, 2012). In a vacuum chamber the only force would be the force of
gravity. Our tests showed that while everyday experience may indicate that not all objects fall toward the earth at the same
rate, they are submitted to the same force of gravity. Our hypothesis is: If gravity has the same effect on all falling bodies then
when air resistance is removed (in a vacuum chamber) all objects will fall at the same rate. Since use of a vacuum chamber will
eliminate air resistance, its use will be the best way to demonstrate the effects of gravity on a falling body.
Materials:
Feather
Stopwatch
Vacuum chamber
Magnet
Coin
Meter stick
Vacuum pump
The vacuum chamber must have some special mechanism so that the fall of any object placed inside of it can be controlled and
measured. Our vacuum chamber had an internal trapdoor that could be opened by waving a magnet nearby.
Safety Precautions:
There are no special precautions needed for this lab.
Methods:
1. Drop a feather and a coin in the open air, three times from a height of 2.5m
2. Time their decent using a stopwatch – record this time in Data Table 1.
3. Drop a feather and a coin in a vacuum chamber – BEFORE evacuating the gases from the chamber, three times from a
height of 2.5m
4. Time their decent using a stopwatch – record this time in Data Table 1
5. Drop a feather and a coin in a vacuum chamber – AFTER evacuating the gases from the chamber, three times from a
height of 2.5m.
6. Time their decent using a stopwatch – record this time in Data Table 1
Results:
Collected data:
All drop heights inside and outside of the vacuum chamber were 2.5m
Data Table 1:
Open-air drop
(s)
Trial 1 Trial 2 Trial 3
Feather (1.23g)
Coin (2.78g)
2.36
1.47
2.42
1.50
2.29
1.48
In chamber (gas-filled)
(s)
Trial 1 Trial 2 Trial 3
2.34
1.49
2.29
1.48
2.34
1.50
In chamber (evacuated)
(s)
Trial 1 Trial 2 Trial 3
1.48
1.47
1.48
1.48
1.47
1.48
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Lab and Report for : Scientific Method, QUALITATIVE Observation, and Writing a Lab Report – Sample Lab Report
Results Continued:
Calculations:
The average time for each type of drop conducted was found by averaging the measurements of the three trials. These
averages will be used for all following calculations, and example is given below.
Example:
2.36s+2.42s+2.29s= 7.07s  7.07s/3 = 2.36s
The averages found through these calculations are given in the following table.
Calculation Table 1:
Open-air drop
Feather (1.23g)
Coin (2.78g)
2.36s
1.48s
2.5
In chamber
(gas-filled)
2.32s
1.49s
In chamber
(evacuated)
1.48s
1.48s
Figure 1
2
Open Air
1.5
Time
(s)
Gas Chamber
1
Vacuum Chamber
0.5
0
Feather Coin
These averages were then used to find the observed acceleration by using a derivative of the basic motion equations:
a=2∆x/ (∆t2) Since the change in position was known to be 2.5m, and the average time was found from the experiment, the
acceleration was easy to calculate for all scenarios.
Example:
a=2∆x/(∆t2)  a=(2(2.5m))/((2.36s)2)=0.89m/s2
These calculations have been completed for all drops and are given in the table below.
Calculation Table 2:
Open-air drop
Feather (1.23g)
Coin (2.78g)
0.89m/s2
9.8m/s2
In chamber
(gas-filled)
0.88m/s2
9.8m/s2
In chamber
(evacuated)
9.8m/s2
9.8m/s2
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Lab and Report for : Scientific Method, QUALITATIVE Observation, and Writing a Lab Report
Discussion:
The findings of the experiment seem to be quite conclusive and clearly let us meet our objective. We intended to show that
gravity applies an equal force on all falling bodies. To do this, we evaluated the trials to find the observed acceleration of the
dropped items. When you look at the acceleration for the falling coin it is nearly the same in all three situations, and very close
to the accepted quantity for acceleration due to gravity.
When you look at the acceleration of the falling feather you can clearly see a different pattern. The feather falling in
the vacuum had nearly the same acceleration as the coin. However, when the feather fell in either scenario where the air was
not removed, it fell at nearly one-tenth of vacuum chamber rate. With such a clear pattern, the slowed acceleration could
easily be attributed to the force of air resistance. This friction-like force would oppose the force applied by gravity and slow the
feather’s decent. Air resistance would have a significantly higher effect on the feather than the coin since the feather has so
much less mass in comparison to its cross-sectional area. There is some implicit error in this procedure because it was nearly
impossible for our lab group to stop any ambient breezes in the lab room. That said, our group had considered this in advance
and therefore we measured the drop time in the non-evacuated chamber as well as in the open-air room for two control
scenarios for comparison. We believe our hypothesis has been supported by the data –that gravity DOES have the same effect
on all falling bodies. Data Table 2 lists supporting evidence of this; note the same drop time for both the feather and the coin
in the evacuated chamber. Looking at all of the data and calculation results it is clear that all falling bodies have the same
effect of gravity applied to them. That said, this may not all ways seem true at first glance because the falling body’s behavior is
still the sum of all forces acting on the body.
Reference
"Falling Bodies" 18 August 2009. HowStuffWorks.com. <http://science.howstuffworks.com/falling-bodies-info.htm>
17 August 2012.
"Free Falling Objects" 27 July 2011. National Aeronautics and Space Administration
<http://www.grc.nasa.gov/WWW/k-12/airplane/ffall.html 17 August 2012.
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