Poster Paper AAPT Meeting, Jan 15-19, 2000, Kissimmee, FL

Michael J. Moloney, Rose-Hulman Institute of Technology

This paper is on line at **http://www.rose-hulman.edu/~moloney**

Computers In Physics and Applied Optics at Rose-Hulman

**Overview**

- Introductory courses (software)
- Excel
- Maple
- Working Model
- Word
- Introductory labs (software and hardware)
- BIB interface to lab equipment
- Files to Excel for processing, graphing, etc.
- CUPS simulation of activating silver with neutrons (prior to doing actual experiment)
- Intermediate Courses
- Theoretical Mechanics
- Maple
- Numerical solutions to differential equations
- Animations of rigid bodies where one Euler angle changes
- Plot of foucault pendulum
- Investigate force and equilibrium, given U(x)
- DOS simulation showing rigid body motion
- in body frame
- in inertial frame
- trajectory in angular momentum space
- Use BIB with shaft encoder to measure coupled oscillations via FFT
- Acoustics
- Vernier MPLI interface with microphone and RH software
- Bar transverse oscillation frequencies via FFT
- Q of tuning fork and resonant cavity via energy decay
- Maple
- Pulse animation on a string (fixed or free ends)
- Membrane animation after being struck
- Matrices used for acoustic transmission through layers of media
- Graphs of bar vibration shapes
- Electromagnetic Theory
- Excel used for iterative solutions to Laplace's equation
- Maple used for optical transmission through a series of layers
- Celestial Mechanics
- Numerical solution to orbit equation
- Quantum Mechanics
- Wave functions and energies for potential wells
- Time evolution of wave packet
- CUPS QM simulation
- Thermodynamics
- DOS software : evolve toward Boltzmann distribution as S increases
- Laser Physics
- CUPS laser simulation
- Solid State Device Physics
- CUPS (SS) simulation showing positive and negative effective mass
- CUPS (QM) simulation showing bands of energy levels
- Physical Optics
- Wave Interference software (from Physics Academic Software)
- Single slit
- Double slit
- Grating
- Circular aperture
- Geometrical Optics
- Software written at Rose-Hulman
- Lens Design
- CODE V software

Students at Rose-Hulman all purchase laptops as freshmen, so every student has a laptop computer.

**Freshman Year**

The great majority of freshmen at Rose-Hulman take a three-quarter sequence of physics courses. Some of these are offered in studio format, and some are in lecture and lab format. In all cases, lecture rooms are capable of projecting a PC screen onto a large screen in the room. This permits students to observe the instructor's screen and be guided in their own work.

The main packages used with freshmen at Rose-Hulman are Excel and Maple V. Sometimes Working Model (WM) is also used. WM is an upgraded version of Interactive Physics, and is outstanding for giving students and faculty a feeling for what goes on through animations and graphs. WM does not show all the equations used, so it is more of a 'black box' than either Maple or Excel.

Excel is probably the most heavily used, because its learning curve is less than that of Maple, and students experience immediate feedback as values and graphs change in response to changing a parameter, and the equations must all be explicity entered.

When integrals or derivatives are needed, Maple is called upon. One- or two-dimensional animations in Maple are very easy to set up (1-D animations require only one command). Animations are inherently interesting to students, and are new to most of the freshmen when presented in physics class.

In elementary kinematics and dynamics, projectile motion is modelled in Excel and / or Maple. Frequently-assigned activities include monkey-and-hunter, graphs of force and potential, projectile motion, and obtaining moments of inertia by summation, in addition to integration.

**Introductory Laboratory**

Students use their own laptop computers to take data in the laboratory. This is done through a simple interface to the PC parallel port (the BIB or Basic Interface Box) I designed in 1994. My original DOS Turbo Pascal data acquisition programs have been extended by Rose-Hulman students to a Visual C++ version for windows. This C++ program can save data to a file. Any analysis, processing, graphing of the data in this file is almost always done in Excel by the students.

The BIB lets students take data from sonic rangers, shaft encoders, analog voltage inputs including microphones, strain gauges, and magnetic field sensors. Most of the work in the freshman year uses the sonic ranger and shaft encoder, with occasional voltage input.

Combinations of inputs can also be used. In one piece of apparatus a shaft encoder is used to record the motion of a slit, and a phototransistor is used to record the light intensity. When a student moves the detector by hand through adiffraction pattern, both intensity and distance are recorded, and the complete intensity pattern is immediately displayed.

Intermediate Courses (see outline above).

For questions or more details email : **moloney@rose-hulman.edu**