Scientific Method Lab

Notes From the teacher

Day 1:

Before class: N/A

In class:

  • Review the lab.
  • Complete the pre-lab – typically you will complete this BEFORE class.

1.Title and date of the lab (remember to add this lab to your table of contents). Include a sub-title: Reaction Rate without a Variable

2.Purpose 1-2 sentences describing the overall goal of PROCEDURE 1; use complete sentences

3.LabProcedure  Write a procedure for Part A. First list the materials that you will be using, then use your own words to describe the steps in experiment in paragraph form.

4.Pre Lab Questions Copy and answer in your lab notebook.

  • Complete the procedure for Part A.

1.Record your data using a table similar to the one provided. Calculate average time for each person.

  • Complete the Analysis Questionsfor Part A. This can be done at home if you do not have time to finish it.

1.Copy and then answer the analysis questions you need to number the question, rewrite the question, and then answer it for full credit.

Day 2:

Before class: Completeall day 1 activities.

In class:

  • Design your own experiment. Make sure to include:

1.Title and date of the lab Provide a sub-title: Design your Own Experiment – Reaction Rate

2.Purpose 1-2 sentences describing the overall goal of your experiment; use complete sentences

3.Hypothesis you need to write 2 hypotheses for this part of the lab:

  • Null Hypothesiswrite a NULL hypothesis
  • Alternate Hypothesis  clear and concise if/then hypothesis

4.LabProcedure  Write a procedure for your experiment. First list the materials that you will be using, then use your own words to describe the steps in experiment in paragraph form. Make sure to create a data table too.

  • Have your design approved by the teacher.

On Your Own / Day 3 (about a week later):

Before Class:

  • Conduct your investigation. In your lab notebook record your data. This data will be due a few days after we do the initial lab in class.
  • Complete the statistical analysis of your data. Include: standard deviation, standard error and chi square values.

In class:

  • Review the statistical analysis of your data. Discuss the formal lab report and rubric.

SCIENTIFIC METHOD INVESTIGATION

Learning ObjectiveTo investigate the effect of environmental factors and/or individual characteristics on reaction time.

Background Information

Reflexes are primarily intended to protect you. Things like blinking your eye, the contraction of your pupil, or pulling your hand back from a hot surface are all reflex actions. Reflexes involve sensory and motor neurons of your peripheral nervous system and often inter-neurons of the spinal portion of your central nervous system. Reflexes don’t require higher brain activity. If you touch a hot surface, you will actually pull your hand back before your brain perceives the heat.

Reactions require higher brain function. Putting your foot on the brake of the car when the car in front of you slows or comes to a stop is an example of a reaction. You must first see the leading car’s brake lights; that information must be processed by your brain and a signal must be sent to the muscles of your back and legs. The signal not only tells you to step on the brake, but how hard to step on the brake.

------

Pre Lab for PART A Typically this is done at home before we do the lab

1.Title and date of the lab (remember to add this lab to your table of contents).

2.Purpose 1-2 sentences describing the overall goal of Part A; use complete sentences

3.LabProcedure  Write a procedure for PART A. First list the materials that you will be using, then use your own words to describe the steps in experiment. This can be in paragraph form or a numbered list as long as it is in your own words.

4.Pre Lab Questions Copy and answer in your lab notebook.

------

PreLab Questions

  1. What are some factors that may cause a person to have a slower reaction time?
  2. What is a reflex action?
  3. When creating an experiment, what are some factors that you would take into consideration to make it a valid lab and to try to ensure you would get reliable data?

------

Procedure

Materials : Meter Stick

Part A – Measuring Reaction Time Without a Variable (In-Class Portion)

  1. A meter stick will be held vertically between the experimental student’s thumb and index finger. The stick should be held so that the 10 cm (.1 meter) mark is between the thumb and index finger.
  2. The lab partner will drop the meter stick and the experimental student must catch it between his/her thumb and index finger as quickly as possible. The distance the meter stick traveled before being caught will be measured (in cm) and recorded on the Data Table (remember to subtract the 10 cm that were below the finger level at the beginning of the experiment) for visual stimuli.
  3. The experimental student will repeat the procedure for a total of 5 trials and then determine the average reaction distance for visual stimuli, recording it on Data Table 1. In your group, you must test 4 people.

Data Table 1: Reaction Distance for Visual Stimuli

Reaction Distance (in cm)
Trial / Person #1 / Person #2 / Person #3 / Person #4
1
2
3
4
5
Average Distance

------

Part A- Analysis Questions(remember to copy the question into your lab notebook first then answer it)

  1. What aspects of the procedure did you keep constant?
  2. Did the results for you and your classmates vary? What aspects of a person do you think could affect their reaction time?
  3. Reaction time is particularly important in driving. What environmental factors could affect a person’s reaction time while they are driving?

**There are no statistical analysis calculations for Part A…just answer the Analysis Questions**

------

Pre Lab for PART B To be done at home before we do this part of the lab.

1.Title and date of the lab. you can call this Scientific Method Lab: Part BDesign your Own Experiment – Reaction Rate

2.Purpose 1-2 sentences describing the overall goal of your experiment; use complete sentences

3.Hypothesis you need to write 2 hypotheses for this part of the lab:

  • Null Hypothesiswrite a NULL hypothesis
  • Alternate Hypothesis  clear and concise if/then hypothesis

4.LabProcedure  Write a procedure for your experiment. First list the materials that you will be using, then use your own words to describe the steps in experiment in either paragraph form or a numbered list. Make sure to create a data table too.

------

Procedure 

Part B - Designing and Conducting Your Own Investigation

Design an experiment to test one other factor that could affect a person’s reaction time. Think about what can affect a person’s reaction time. Some possibilities are dominant hand (right vs. left), athleticism, musical ability, reaction rate while texting, while listening to loud music, while having a conversation and using only peripheral vision….there are lots of options. Brainstorm with your group and figure out something to test.

In designing your experiment, you want to use a similar protocol to the one we conducted during Part A of the lab. Figure out your independent variable, come up with parameters for your experiment, and create a data table. Don’t forget to consider what your controls are going to be. Also, so that you can do a full statistical analysis of your results you want to test at least 20 people. If you are testing the same person for two set-ups (ex. dominant hand vs. non-dominant hand), you want to do three trials (at least) for each category.

------

Part B -Analysis Questions

  1. What was your independent variable? What is your dependent variable?
  2. What is the chi square equation?
  3. What is a null hypothesis?
  4. Did your variable have a significant effect on reaction rate?

------

Part B – Statistical Analysis

Complete a statistical analysis that includes the standard deviation, standard error and chi square values. See the statistical analysis packet for help with this. You need to show all your work for ALL your data (not just the data you collected individually, but all of your group data).

**YOU WILL ALSO BE DOING A FORMAL LAB WRITE UP IN YOUR LAB GROUP FOR THIS EXPERIMENT **

Scientific Method – Reaction Rate Lab - Rubric

_____ / 1Title and Cover Page

-Cover page includes a title, YOUR names, block, and due date.

_____ / 7Abstract

-Conveys an overview of the experiment CONCISELY

-Research problem and hypothesis

-General procedure

-Overall findings

-Accept/ Reject null and summary sentence of what was concluded

-This section should be short (about 1 sentence for each of the above requirements)

_____ / 8Introduction

-Defines the research problem and overall scientific concept of the lab

-States the alternate hypothesis and also the null hypothesis

-Background information on how reactions happen in humans (separate paragraph)

-Background research relating to YOUR topic (ex. The effect of … on reaction rate) →find research that has been done relating to your experiment (separate paragraph)

-You need 2 in-text citations (put the full citations in Appendix C)

_____ / 4Methods

-Gives enough details to allow for replication of procedure (number of participants, actual procedure, number of trials, etc)

-Include the dependent and independent variables

-Include the parameters of the tests subjects (what were the constants?)

-Statistical analysis tests that were performed (don’t explain HOW to do them, just say which ones you did)

-Paragraph form (NOT bullet points)

______/ 7Results

-Intro paragraph (short!) of overall findings of the lab

-Table with averages, standard deviation, standard error, and chi square values

-Explain the table in words – shortly

-Put all the raw data and all your calculation in the APPENDIX…not in the results!

-This section should NOT be very long….you are to DISCUSS your results and what they mean (ex. Accept/ reject null) in the DISCUSSION section…not in the results

_____ / 10Discussion

-Accept or reject null hypothesis and WHY (chi square value, critical value of P)

-Analysis of data and what it suggests

-Was your alternate hypothesis correct? (if you accepted the null, then no it wasn’t)

-Overall findings of the lab

-Problems encountered in the lab, errors found, and ways to improve the experiment the next time around (separate paragraph)

-The discussion should be rather long with all your data analysis

_____ / 6Conclusion

-Summary paragraph explaining what you have found

-Describe what else has been learned in this lab (designing an experiment, statistical analysis, etc)

-This section ONLY may be in first person

_____ / 4Appendix

-Appendix A → Raw Data (table form)

-Appendix B → Calculations (SHOW WORK!!) – they may be hand written NEATLY (don’t give me a messy rough draft)

-Appendix C → Bibliography with CORRECT and full citations

_____ / 3Presentation

-No first person (except conclusion)

-Sections are labeled with headings

-Paragraph form throughout (separate paragraphs if needed – especially introduction and discussion)

-Grammar and spelling are correct with evidence of proofreading

-Report is written in scientific style – clear and to the point

-Formatted correctly: 12 point font, Times New Roman, 1.5 spacing, and 1 inch margins

_____ / 50Overall Grade **** Attach this sheet to the BACK of your Lab Report****