Schneider, 2014-2015

Physics Lab Procedures

No food or drink at lab stations.Stay at your lab bench, working with your lab group.

“Consultations” with others ok. Socializing is not.No “out of classroom experiences.”Focus on the experiment.Treat equipment and supplies gently and respectfully.You are dismissed from your lab bench back to your

desk after:All data is collected and recorded.All materials are properly cleaned and stored.All waste/garbage is disposed of or recycled.You get the “ok” from me.

During Lab

Systematic approach to doing science

Clearly articulate process and thinking

YOUR intellectual property

Lab Notebooks: What’s the point?

Purpose: Statement of problem to be investigated

Equipment diagram: Include all components of the system and the variables measured.

Procedure: Identify and name all variables. (What you are measuring) Identify measurement tool that will be used for each variable. State precision and units of each type of measurement.State how many conditions will be run (hint: 10) and how

many trials for each condition (hint: at least three).General procedure / plan.

Data Table: All rows & columns labeled, with units

Lab Notebooks: Day of Lab

MUST result in USABLE data!

Evaluation of DataResults Table (Post-lab Calculations)

All columns and rows labeled, with units. Include uncertainty calculations – if applicable.Watch sig figs!Show example of “out-of-the-ordinary” calculations

Can be a separate Title: “Sample Calculations”Graphs

Must include: title, axes labels (with units), axes scales

If appropriate: best fit line(s), relevant equation, data labels

Lab Notebooks: Post Lab

Scientific ExplanationClaim: The answer to your question. A

statement that shows understanding of a phenomenon.

Evidence: Scientific data that supports the claim.

Reasoning: Justification that links the claim and evidence using scientific principles or ideas.

Lab Notebooks: Post Lab

CLAIMDescribe (in words) any relationship(s)

between variables identified in the purpose. A statement that shows understanding of

the phenomenon observed in the lab.

Write any mathematical relationships derived from graphical analysis.Use variables specific to the experiment –

not “x” and “y”Include appropriate units

Lab Notebooks: Scientific Explanation

POST Lab

CLAIM – example from Circle LabFor a circle, area has an exponential

relationship with diameter. As diameter increases, area increases exponentially.

The relationship developed in this lab is represented by the mathematical model:

The units for area are boxes2 and the units for diameter are boxes.

Lab Notebooks: Scientific Explanation

POST Lab

EVIDENCEExplain how the model was derived.

Refer to relevant data or results tables and/or graphs.

State the meaning of the slope and y-intercept.Refer to relevant graphs.

Explain any unexpected results / outcomes.I.e. Error analysis. NOTE: Not “human error”! Be specific!

Lab Notebooks: Scientific Explanation

EVIDENCE – example from Circle LabThe area for each circle was plotted vs. the

corresponding diameter. See data in Table 1. The original graph showed an exponential

relationship (Graph 1), so was linearized by squaring the parameter on the x-axis – the diameter. (Graph 2).

The slope represents the change in area divided by the change in diameter2 and is a unit-less value.

The units for area are boxes2 and the units for diameter are boxes.

Lab Notebooks: Scientific Explanation

POST Lab

REASONING:

Relate the claim and evidence to known scientific principles or ideas.

Lab Notebooks: Post Lab

REASONING – example from Circle LabFrom what is know regarding the model for

area – the resulting value is equal to = 0.78.

This corresponds well to the value predicted in this lab, 0.73.

Lab Notebooks: Scientific Explanation

POST Lab

Claim: The answer to your question. A statement that shows understanding of a phenomenon.

Evidence: Scientific data that supports the claim.

Reasoning: Justification that links the claim and evidence using scientific principles or ideas.