- By
**gen** - Follow User

- 102 Views
- Uploaded on

Download Presentation
## PowerPoint Slideshow about 'Discovery Labs in Physics' - gen

**An Image/Link below is provided (as is) to download presentation**

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript

Transformation of Intro Labs

- We have used an NSF CCLI matching grant to transform intro physics labs from “cookbook” to “discovery” format.

Cookbook Labs

- The “cookbook” lab manual directs the student through the lab. The student is basically a technician rather than a scientist.

SHM - Cookbook

Lab Notebook. Keep notes for this experiment in your lab notebook.

Data Acquisition. Use M in the range from 50 g to 500 g.

Include the mass of the mass holder in the value of M.

To get an accurate value of T measure the time for 20 periods.

(Note: begin the count at the end of the first period.)

Be sure that you estimate the uncertainties in both T and M.

SHM – Cookbook (2)

Data Analysis. Plot T2 (on the y-axis) vs. M (on the x-axis).

Find the slope of this line and the uncertainty in this value.

Find the y-intercept of this line and the uncertainty in this value.

Write the experimentalequation which relates T2 and M.

SHM – Cookbook (3)

Results.

Based on the linear fit values, what is the experimental value of k and its uncertainty?

What is the physical meaning of the y-intercept, b?

Motivation for Change

- Brightest students considered the course to be boring.
- Course did not help develop conceptual understanding.
- Course did not develop critical thinking.

Discovery

- The “discovery” method involves the student actively in the learning process. The student does science.

Discovery

- Student-centered.
- Develop conceptual understanding.
- Develop critical thinking.
- Encourage experimentation and imagination.
- Encourage teamwork.

The pre-lab exercise introduces students to the basic theory.

Physical Pendulum. The period of a physical pendulum for small angles is given by the following equation:

Period = 2p (I/mgd)0.5

where m is the mass of the pendulum, d is the distance between the center of mass and the center of rotation, and I is the moment of inertia about the center of rotation.

Discovery – Pre-LabBefore making measurements, students are asked to make predictions

Consider a physical pendulum made up of two identical masses connected to a low-mass rod. The pendulum rotates about the center of the low-mass rod.

d2

center of rotation

d1

Discovery - PredictionThese predictions are recorded as part of the experiment

In your lab notebook, describe how the period will change as d2 is increased. Assume d1 is at its maximum value. Explain why the period changes in this way

d2

center of rotation

d1

Discovery - PredictionMeasurements are made to test the predictions.

Set the lower mass near its lower end (i.e. d1 equals 18 cm) and the upper mass just below its upper end (i.e. d2 equals 17 cm).

Measure the period of oscillation for small angles.

Repeat the period measurement for two other positions of the upper mass.

Record the values of d1 & d2 and the measured period in your lab notebook.

Discovery - MeasurementStudents compare predictions and measurements to test their understanding of the physical phenomena.

In your lab notebook, compare calculated and measured values of the period of this physical pendulum. Do the predicted and measured values agree?

Discovery - AnalysisConclusion - Pros

- More interesting.
- Students learn concepts better.
- Students get more hands on experience.
- Greater instructor satisfaction.

Conclusion - Cons

- Less graphical analysis.
- More work for instructors.
- Appropriate hardware and software is required.

Download Presentation

Connecting to Server..