Pendulum Projectile Target Lab
Grade Level/Subject
11th grade physics
Unit
Energy
Enduring
Understanding
The movement of an object can be analyzed and predicted using
mathematical relationships that exist among position, velocity,
and acceleration.
Energy can be transformed from one form to another
SOL Objectives
PH.1
PH.5
PH.8
The student will plan and conduct investigations in which
c) information is recorded and presented in an
organized format;
h) appropriate technology including computers,
graphing calculators, and probeware, is used for
gathering and analyzing data and communicating
results.
The student will investigate and understand the
interrelationships among mass, distance, force, and time
through mathematical and experimental processes. Key
concepts include
c) projectile motion;
The student will investigate and understand that energy
can be transferred and transformed to provide usable
work. Key concepts include
a) transformation of energy among forms including
mechanical, thermal, electrical, gravitational,
chemical, and nuclear;
Title
Pendulum Projectile Target Lab
Lesson Objective
Students will predict where a projectile will land and then test
the prediction.
Inquiry Level
3 – Students are provided with an objective and required
equipment, but are not given a method for solving the
problem.
Materials Required
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Pendulum apparatus
Thread or fishing line
Razor blade
~200 g mass
Paper target (small paper plate or half sheet of paper)
Meter stick
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Teacher Supplemental
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You don’t need to tell students to use energy to solve the first part of this problem,
although it should be fairly obvious if the lab is done during the energy unit.
Students typically have a harder time remembering how to work with projectile motion
problems.
This lab could easily be changed to level 2 inquiry by providing explicit instruction about
how to approach the problem.
Lead fishing weights work well as projectiles. There is no need to use your more
expensive brass masses; they will only get damaged when they hit the floor.
It may be a good idea to remove the razor blade and only attach it when each group is
ready to do their test run. I have found it fast and easy to tape the blade to a small flat
piece of wood. I can then simply clamp the blade to the pendulum and easily remove it
when finished.
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Pendulum Projectile Lab
PROCEDURE: This apparatus functions as any normal pendulum except that
when the bob reaches the bottom its string will be sliced by the razor blade.
This device is designed to operate like any normal pendulum except that when
the pendulum bob reaches the bottom its string will be sliced by a razor blade.
The pendulum bob will then become a projectile.
You will find a pendulum clamped to your lab table. CAUTION!! Be very careful
with the pendulum apparatus. The attached razor blade is extremely sharp!
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YOUR GOAL WILL BE TO PREDICT WHERE THE BOB WILL LAND.
Take your measurements and do your calculations. Show your work on the back of this page.
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Tape your target paper to the floor in the spot where you predict the bob will land.
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You are allowed only one test run. Your teacher must witness your test run.
IF YOU HIT THE TARGET then you may turn in your paper as is. (Each student must turn in their own
paper with all of the work shown.) You will earn full credit as long as the work is shown clearly and
neatly.
We Hit The Target!!! Your teacher’s initials _______
IF YOU MISS THE TARGET then you must turn in a complete lab report to receive full credit.
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Your lab report will include the following sections:
Procedure (One paragraph in complete sentences)
o Describe the procedure that you used to calculate where the bob would land.
o Write as if you are explaining this to someone who has not studied physics.
Measurements and Data (Must be neat and organized)
o List any data that you collected.
o Describe the tools that you used. (i.e., did you use a bathroom scale or a digital scale that is
accurate to 1/1000 gram)
Calculations (Must be neat and organized)
o Include any equations that you used. Write a statement explaining why you used it and what
data it provided for you.
o Show your calculations.
Discussion (One paragraph in complete sentences)
o Discuss your results. Discuss factors that may have contributed to the inaccuracy of your
answer. Be specific. If the phrase “human error” occurs anywhere in your lab report, it will be
returned to you without a grade!
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