Lecture on ATAT's Version 7 Science Portion: Scientific Reasoning

Introduction

• Focus on the metric system and scientific reasoning.
• Key topics include measurement units, empirical evidence, variables in experiments, cause and effect, and the scientific method.

The Metric System

• Standardized method of measurement: Based on the decimal system.
• Units:
  • Length: meters
  • Mass: grams
  • Volume: liters
• Mnemonic: "King Henry Doesn't Usually Drink Cold Milk" helps remember metric prefixes from kilo to milli.
  • Right (smaller units):
    • Deci (÷10)
    • Centi (÷100)
    • Milli (÷1000)
  • Left (larger units):
    • Deca (×10)
    • Hecto (×100)
    • Kilo (×1000)
• Conversion involves moving decimal place left or right.

Measurement Tools

• **Length:
  • Ruler: Short distances, up to 30 cm/12 inches.
  • Tape Measure: Longer distances, up to 25 feet.
  • Calipers: Precision for small objects.
• Mass:
  • Balance Scale: Compares mass.
  • Digital Scale: Precise measurement, e.g., for recipes or chemicals.
  • Spring Scale: Uses gravity for mass.
• Volume:
  • Graduated Cylinder: Accurate liquid volume.
  • Measuring Cup: For liquids and bulk solids.
  • Pipette: Transfers small liquid amounts.**

Choosing Metric Units

• Length:
  • Millimeters: Small measurements.
  • Centimeters: Everyday objects.
  • Meters: Larger distances.
  • Kilometers: Geographical distances.
• Mass:
  • Milligrams: Very small weights.
  • Grams: Small items.
  • Kilograms: Larger weights like body weight.
• Volume:
  • Milliliters: Small volumes.
  • Liters: Larger liquid quantities.
  • Kiloliters: Large capacities like swimming pools.

Empirical Evidence

• Obtained through: Observation, experimentation.
• Qualitative Data: Descriptive, involves patterns, colors, textures.
• Quantitative Data: Numerical, measures length, height, quantities.

Variables in Experiments

• Independent Variable: Manipulated by researchers.
• Dependent Variable: Measured response to independent variable.
• Controlled Variables: Conditions kept constant.
  • Example: Sunlight's effect on plant growth.

Cause and Effect Relationships

• Cause: Independent variable.
• Effect: Dependent variable.

Scientific Method

1. Observation: Derived from senses.
2. Research: Provides background, consult reliable sources.
3. Hypothesis: If-then statement predicting outcome.
4. Experiment: Includes data collection, defines variables.
   • Independent variable is manipulated.
   • Dependent variable is measured.
   • Control group provides baseline.
5. Conclusion: Interprets data to support/reject hypothesis.
6. Sharing Results: Through journals, conferences.
7. Repetition and Verification: Ensures reliability and accuracy.

Final Thoughts

• Understanding scientific reasoning is critical for success on the TEAS exam.
• Additional resources available for further study.