Pendulum Projectile Target Lab

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 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.
PH.5 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;
PH.8 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 / ·  Pendulum apparatus
·  Thread or fishing line
·  Razor blade
·  ~200 g mass
·  Paper target (small paper plate or half sheet of paper)
·  Meter stick

Teacher Supplemental

·  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.

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!

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.

·  Tape your target paper to the floor in the spot where you predict the bob will land.

·  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.

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!

1